Technical ReportPDF Available

Growing oats in Western Australia for hay and grain

Authors:
  • Department of Primary Industries and Regional Development Western Australia
  • Department of Primary Industries and Regional Development

Abstract and Figures

The oat industry in Western Australia has made phenomenal progress in recent years with the discovery of new markets, the release of several high yielding varieties and the development of agronomic guidelines through rigorous research programs. Oat production in Western Australia for the domestic and export market has significantly increased over the past few years. Oats are now regarded as one of the most profitable cropping enterprises. Oat production is mainly export orientated and thus has a substantial economic influence on the agricultural industry. In Western Australia, oats are predominantly grown for grains, for milling and feed, and for hay. As oats are versatile in their rejuvenation they also offer an opportunity for grazing before they are cut for hay or harvested for grain. Oats also play an integral role in farming systems due to their rotational benefits. Being predominantly cereal based, export hay fits into most of the accepted cropping rotations and helps to reduce weed seed banks, overcomes herbicide resistance and provides a break from traditional chemical regimes in addition to giving growers an alternative cash crop. Cutting oats for hay effectively reduces the risk of Annual Ryegrass Toxicity (ARGT) as ryegrass plants (and other hosts) are removed from the paddock prior to toxin formation. Furthermore, oats have a greater tolerance to waterlogging and frost than other cereals. West Australian oats are reputed to be of the highest quality in the world and they successfully meet the requirements for human and animal consumption. As international buyers, such as Japan, become increasingly focused on the quality of oats, it is important that West Australian growers continue to supply produce that meets premium standards and expectations. Sound, research-supported agronomic management is essential to produce quality grain oats and oaten hay that meets the expectations of growers and buyers. This bulletin provides the industry with a practical management guide to produce high quality and profitable oat crops for grain and hay. The bulletin also helps growers to evaluate the viability of including oats in their cropping system. The bulletin highlights some important in and out of paddock issues and suggests some agronomic guidelines for successful oat production
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Growing oats in
Western Australia
for hay and grain
Bulletin 4798
August 2011
ISSN 1833-7236
Acknowledgements – The authors wish to thank the Grain
Research and Development Corporation (GRDC) and Department
of Agriculture and Food Western Australia (DAFWA) for the
funding of various Oat Agronomy Projects
The information contained in this Bulletin is based on the
work conducted by many research scientists, development
officers and plant breeders. The authors would like to thank
the following groups of people from the Department of
Agriculture and Food, Western Australia.
Oat Agronomy project team: Blakely Paynter, Raj Malik,
Kellie Winfield, Jocelyn Ball and Cindy Webster
Plant Pathology: Roger Jones Geoff Thomas, Vivien
Vanstone and Dominie Wright.
Plant Nutrition: Ross Brennan.
Entomology: Svetlana Micic and Chris Newman
Integrated Weed Management: Abul Hashem, John Moore
Research Support Units: Katanning (especially Vince
Lambert), Northam and Wongan Hills
We also greatly acknowledge the photo contributions from Dr
Rob Loughman, Principal Research Officer, DAFWA; and from
Dr Pamela Zwer, Principal Oat Breeder and John Sydenham,
Technical Officer, National Oat Breeding Program.
Finally, we give special thanks to Ian Pritchard, Senior Grain
Extension Officer, Dr Peter White, Project Manager. Their insights
were crucial in instigating and finalising this bulletin.
Raj Malik Cindy Webster Amelia McLartyBlakely Paynter
Compiled and edited by Raj Malik, Blakely Paynter, Cindy Webster and Amelia McLarty.
Department of Agriculture and Food, Western Australia
Growing oats in
Western Australia
for hay and grain
Raj Malik, Blakely Paynter, Cindy Webster and Amelia McLarty
Department of Agriculture and Food, Western Australia
Bulletin 4798
August 2011
Page 2
Copyright © Western Australian Agriculture Authority, 2010
Copies of this document are available in alternative formats upon request:
3 Baron-Hay Court, South Perth WA 6151
Tel: (08) 9368 3333
Email: enquiries@agric.wa.gov.au
<www.agric.wa.gov.au>
Disclaimer
The information, representations and statements contained in this publication are provided for general
scientific information purposes only.
The State of Western Australia, the Minister for Agriculture and Food, the Director General of the Department
of Agriculture and Food, the Grains Research and Development Corporation and their respective officers,
employees and agents:
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the information, representations or statements in this publication (including but not limited to information
which has been provided by third parties).
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an act or failure to act by any person in using or relying on any information, representation or statements
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Users of any chemical product should always read the label on the product before use and should follow
the directions specified on the label.
Acronyms
ADF Acid detergent fibre
ARGT Annual ryegrass toxicity
ATP adenosine triphosphate
BYDV Barley yellow dwarf virus
CCN Cereal cyst nematode
CP Crude protein
DM Dry matter
DMD Dry matter digestibility
DTPA diethylene triamine penta acetic
acid
estME Estimated metabolisable energy
EPR End point royalty
IVD in-vitro digestibility
MRL Maximum residue limit
NDF Neutral detergent fibre
RLN Root lesion nematode
SARDI South Australian Research and
Development Institute
WSC Water soluble carbohydrates
A Plant Breeders Rights (PBR)
protected variety
Contents
Page 3
Contents
Important tips for producing quality hay.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. . 5
Important tips for producing quality oat grain .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. . 7
Introduction .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. . 8
Paddock selection.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. . 9
Soil characteristics .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. . 9
Rotation . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 10
Crop establishment . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 11
Variety selection.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..11
Sowing .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..11
Fertilisers and plant nutrition .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..16
Nitrogen . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..16
Phosphorus .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 22
Potassium . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 23
Sulphur . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 23
Micronutrients – zinc, manganese and copper . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 24
Manganese.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..25
Weeds.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..26
Diseases .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..29
Foliar diseases.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..29
Virus Diseases . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 31
Chemical control of foliar diseases . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 34
Root and crown diseases . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 34
Nematodes.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..35
Soil and plant testing services.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 39
Insect and allied pests of oats. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..40
Stored grain pests.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 46
Harvest .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 47
When to direct harvest grain . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 47
When to swath grain.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..47
Storage of grain oats .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..47
Making quality hay.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..48
Choice of variety .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 48
Quality parameters for hay .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..48
Hay cutting time.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 50
Baling.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..54
Storing hay .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 54
Further reading .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..55
Appendix 1. Zadoks growth scale .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ..57
Page 4
Export hay – Talk to your local hay processor before sowing oats for
export hay. Hay processors have different requirements which will
affect how you manage your crop. Your processor can advise you
about their requirements for the production of export hay
• ARGT management – Look to implement an annual ryegrass toxicity
(ARGT) management plan through the introduction of the twist fungus
or Safeguard A ryegrass (Farmnote 417/2010). There is nil tolerance of
ARGT for export and with export hay becoming a prescribed product,
testing for ARGT will become compulsory.
• Soil test – As hay crops remove substantial amounts of nutrients, it
is important to soil test paddocks, particularly those where hay is
regularly grown.
• Seeding rate – Target 240 to 320 plants/m2 (110 to 150 kg/ha depending
on grain size). Higher is not always better as it can lead to reduced
stem thickness in inherently narrow stemmed varieties like Wintaroo A.
Higher seeding rates do offer better weed competition and generally
lead to increased hay yield.
• Paddock preparation – Roll paddocks after seeding but before the start
of tillering (reduces contamination).
• Potassium fertiliser – Applying potash can improve both hay yields
and hay quality. Potassium can improve quality by decreasing stem
fibre (ADF and NDF) levels and in situations where inadequate nitrogen
fertiliser has been applied, increase water soluble carbohydrates.
Varieties appear to react similarly to potassium application.
• Nitrogen fertiliser – Do not apply excessive levels of nitrogen as it may
decrease hay quality by increasing stem fibre levels (ADF and NDF) and
decreasing water soluble carbohydrates. Varieties may differ in their
response to applied nitrogen.
• Row spacing – Maximum row spacing for oaten hay is 180 mm. This
assists with keeping the hay swath off ground.
• Cutting date risk – Sowing date and variety maturity can be used to
minimise the risk of all your hay being on the ground at the same
time. Spreading the sowing date of a variety over a week or so; or
sowing two varieties of differing maturity can reduce the risk of weather
damage due to adverse weather conditions after cutting.
Important tips for
producing quality hay
Important tips
Page 5
• Disease – In high disease risk areas where a susceptible variety has
been sown, early label applications of a registered fungicide may lower
the impact of disease infection on the physical appearance of hay for
export.
• With holding periods – Only apply registered herbicides and fungicides
in accordance with the label registrations as some export markets such
as Japan have recently introduced Maximum Residue Limits (MRL) in
feed products. Do not apply a herbicide or fungicide within a withholding
period before cutting.
• Contractors – Talk in advance to your contractor about the suggested
cutting date so that machinery is available at the crucial cutting time.
• Cutting stage – Cut hay at the watery ripe stage (Z71). This usually
occurs in late September to early October with a May planted crop.
A later cut gives a yield advantage but quality drops. Quality may be
better when cutting early but there are yield penalties. Cutting at the
watery ripe stage is the best compromise between high yield and high
quality. Varieties with good colour like Wintaroo A need to be monitored
carefully, to make sure that they are cut at the right stage.
• Cutting height – Cut hay at least 15 cm high. If stems are thick, cut a bit
higher to reduce fibre content.
• Super conditioners – The use of super conditioners can reduce the risk
of weather damage by reducing the interval between cutting and baling
from 10 to 14 days down to 4 or 5 days. In good drying conditions
however, super conditioning can result in hay becoming too dry and
make it difficult to form a good bale.
• Baling – Bale when moisture has dropped to between 12 and 14 per
cent.
• More information – For more detailed tips on growing high quality oaten
hay read this publication: Zwer, P & Faulkner, M 2006. Producing Quality
Oat Hay, RIRDC publication 06/002. Available at http://www.rirdc.gov.
au/reports/FCR/06-002.pdf.
Important tips for
producing quality hay
Important tips
Page 6
• End use - Decide on whether you are growing for milling or feed.
• Receival standards - Make yourself aware of the oat receival standards
and quality segregations. Full details of oat receival standards can be
obtained from CBH. (www.cbh.com.au). The oats are segregated into
two grades - Oat 1 (formerly milling) and Oat 2 (formerly feed) - to reflect
the quality and the markets into which these segregations are sold.
• Varieties - Consider varieties which are suitable for the targeted end use
and quality. Then compare the relative yields and/or gross margins of the
varieties by end use and quality. Assess risk factors of specific varieties
such as disease, lodging risk, shedding risk and quality issues. Check
with buyers before selecting a variety for a particular market.
• Soil type - Oat grain crops grow more favourably in medium textured
soils with good water holding capacity and medium to high fertility levels.
Also, avoid low lying paddocks to avoid waterlogging or severe frost
incidents.
• Seed size - Always sow plump seed - certified or otherwise. Plump seed
contains more food resources that promote the establishment of strong
healthy seedlings.
• Date of seeding - Sowing time should be matched to the maturity of
chosen variety to ensure the plant flowers at its optimum time and
reaches its maximum yield potential. Crops sown too early or too late
may not achieve optimum growth resulting in lower yield and quality.
Long season varieties should be sown first (late April to mid-May) and
short-mid season varieties later (late May to mid June).
• Seed dressing - Always treat seed with a suitable fungicide seed dressing
when appropriate. Seed dressings provide protection against smuts
particularly loose smut and bunt diseases.
• Disease - There are limited fungicide options for oats. For control of rusts
(stem and leaf) apply a label rate of propiconazole or tebuconazole. For
suppresion of septoria apply a label rate of propiconazole. Always follow
label recommendations.
• Seeding rate - Maintain a plant density of 240 plants/m2 with a row
spacing of 18cm. This combination promotes good ground cover. If
weeds are a serious issue consider increasing plant density to help plants
compete better with weeds. Higher plant densities also compensate for
the lack of tillering experienced in waterlogged conditions.
Important tips for
producing quality oat grain
Important tips
Page 7
• Seeding depth - Sow seed 3-6 cm deep (coleoptile length) using press
wheels. The press wheels will compress the soil directly above the
seed ensuring even seeding depth, and may also help overcome water
repellent soils.
• Soil test - Soil testing is essential before applying fertilisers. For a healthy
crop, both macro and micro nutrients are needed in adequate amounts.
Pay special attention to soil test results if hay was grown previously
in the same paddock because hay removes substantial amounts of
nutrients particularly potassium from the soil.
• Fertiliser - Ensure phosphorus levels are adequate for good growth and
to reduce the risk of screenings and to improve hectolitre weight and
groat %. Nitrogen and potassium are complementary to each other
in improving yield and quality and thus both are needed in adequate
amounts to take full economic advantage.
• Weed control - Pre-seeding weed control is vital as in-crop weed control
options are limited.
• Insects - In high risk aphid years (with a summer/autumn green bridge or
in disease prone regions), anti-feeding insecticides (alpha-cypermethrin)
should be applied at 3 and 7 weeks after emergence regardless of
whether aphids can be seen on the plants
• Harvest - To reduce shedding losses harvest the crop as soon as it ripens
and has grain moisture, less than 12%.
• Storage - Store the oats in clean, dry water proof silos, the maximum
moisture content at which oats can be safely stored is 12.5%.
• Insects in stored grain - Inspect stored grain for insects at least
once a month to prevent any severe infestation. Information on
the control of stored oat grain pests can be found on the DAFWA
website www.agric.wa.gov.au and the GRDC stored grain website
www.storedgrain.com.au
Important tips for
producing quality oat grain
Important tips
Page 8Introduction
Introduction
Raj Malik, Cindy Webster
The oat industry in Western Australia has made phenomenal progress in recent years
with the discovery of new markets, the release of several high yielding varieties and
the development of agronomic guidelines through rigorous research programs. Oat
production in Western Australia for the domestic and export market has significantly
increased over the past few years. Oats are now regarded as one of the most profitable
cropping enterprises. Oat production is mainly export orientated and thus has a substantial
economic influence on the agricultural industry.
In Western Australia, oats are grown for grain, for both milling and feed, and for hay. As
oats are versatile in their regeneration they also offer an opportunity for grazing before
they are cut for hay or harvested for grain. Oats also play an integral role in farming
systems due to their rotational benefits.
Export hay fits into most of the accepted cropping rotations and helps to reduce weed
seed banks, overcomes herbicide resistance and provides a break from traditional
chemical regimes in addition to giving growers an alternative cash crop. Cutting oats
for hay effectively reduces the risk of ARGT as ryegrass plants (and other hosts) are
removed from the paddock prior to toxin formation. Furthermore, oats have a greater
tolerance to waterlogging and frost than other cereals.
West Australian oats are reputed to be of the highest quality in the world and they
successfully meet the requirements for human and animal consumption. As international
buyers, such as Japan, become increasingly focused on the quality of oats, it is important
that West Australian growers continue to supply produce that meets premium standards
and expectations.
Sound, agronomic management is essential to produce quality grain oats and oaten hay
that meets the expectations of growers and buyers.
This bulletin provides the industry with a practical management guide to produce high
quality and profitable oat crops for grain and hay. The bulletin highlights some important
in and out of paddock issues and suggests some agronomic guidelines for successful
oat production.
Introduction
Page 9
Paddock selection
Selecting the appropriate paddock is fundamental for producing high quality hay and
oat grain crops. Consider selecting paddocks that:
are not prone to long periods of waterlogging. Despite having a higher tolerance than
other cereals, long periods of perched water within 30 cm of the soil surface can
reduce potential yields by 60 per cent.
have minimal weed burdens and are capable of a double knockdown before seeding.
do not have a history of rhizoctonia bare patch, take-all, ryegrass and doublegee.
There is a zero tolerance against ARGT in export hay.
Also avoid paddocks with the following characteristics:
a history of leaf (foliar) disease in the previous oat crop. Try to break up the disease
cycle with a suitable crop rotation as there are very limited fungicide options to control
foliar diseases in oats.
a low pH < 4.5 or high salinity and compaction
covered with large stones, carcasses, tree branches, heavy crop
residues and other foreign objects that may contaminate
the hay and result in downgrading or rejection of export
hay. Paddock preparation (that is, removing these
contaminants) plays a major part of management.
The detrimental effect of herbicide residues from
preceding crops must be considered in the decision
to grow oats in rotations. Oat plants are sensitive
to sulfonylurea (SUs), imidazolinone and triazine
residues. Where residual herbicides have been
used on prior crops during drier seasons, a
test at sowing can confirm if the residues will
harm the oat crop.
Soil characteristics
Oats grown for grain and oats grown for hay
require slightly different soil characteristics
for their optimal production.
Oats for grain should be sown in soils with
medium to high soil fertility. In contrast, oats
for hay should be sown in soils of moderate
fertility only, in the range of 80 kg/ha and less of
available nitrogen (N) in the top 60 cm at sowing.
On highly fertile soils oaten hay crops produce
greater biomass rather than quality hay. This can
affect the dollar returns for the paddock because
quality ultimately determines the final price.
To avoid lodging, hay crops should be sown in paddocks
where the soil is expected to have low N mineralisation rates,
from previous pasture legume stubbles and pulses.
Oaten grain crops grow more favorably in medium textured soils with greater
water holding capacity.
All oat crops, irrespective of whether they are grown for grain or for hay, require deep
well-drained soils with at least 0.5 m of suitable root zone.
Introduction
Page 10
Rotation
Canola is an ideal break crop for oats because it provides an excellent opportunity
to reduce grass weeds and minimise foliar and root diseases for hay. One should be
cautious if using residual herbicides for weed control in canola; stubble residue must be
managed to avoid contamination.
After a good medic (Medicago) pasture stand or a high biomass pulse/low yielding pulse
crop on heavy soils it is likely that the high soil nitrogen levels may increase the acid
detergent fibre (ADF) and the neutral detergent fibre (NDF) contents and the likelihood of
lodging in hay crops, especially in tall varieties. However, on lighter soils and or following
a weaker pasture legume base or high yielding pulse crop, lodging will not be an issue
with tall varieties. Conversely when growing oats for grain, high soil nitrogen will be more
of an advantage as it will increase grain yield and any reduction if any in grain quality is
not so much of an issue.
Frost risk management
Although oats are considered to be tolerant to frost, some damage can still occur in
Western Australia. The most damaging stage for frost is after ear emergence. If anthers
are damaged during ear emergence, sterility may result. The grain can become shrivelled
if the frost event occurs during the milky ripe stage.
To minimise the chance of a crop being frosted, avoid high risk areas of paddocks, such
as valley floors. Sow as late as possible in the range of optimum
sowing dates so that the plant flowers in its optimum
window but as late as possible.
Crop establishment
Page 11
Crop establishment
Raj Malik, Cindy Webster
Variety selection
The following factors should be considered before deciding which variety to sow:
end use -milling, feed or hay
yield - relative yield of milling, feed and hay varieties
adaptation - suitability of the variety for a particular Agzone.
Other considerations when selecting varieties include maturity, disease resistance,
lodging resistance and quality aspects.
In2006themillingandfeedoatsegregationswererenamed‘Oat1’and‘Oat2’tobetter
reflect the quality of oats and the markets into which these segregations are sold.
Oats for milling (Oat 1) are received on the basis of grain physical quality including
hectolitre weight, free groats, screenings and moisture. Unlike other cereals there are no
receival standards for protein and colour.
The receival requirement for Oat 1 grade are a minimum hectolitre weight of 51 kg/hL and
screening levels (< 2.0 mm) less than 10 per cent. The receival requirement for Oat 2 is
a minimum hectolitre weight of 49 kg/hL.
There is no limit on screenings for Oat 2
deliveries. The moisture level should be
less than 12 per cent for both categories.
Full details of receival specifications
can be obtained from the CBH Group
(www.cbh.com.au)
The export hay market is very much a
niche market that is driven by high quality
and consistent supply. Over the past few
years the major buyers of Australian hay
have been the Asian markets, particularly
Japan, South Korea and Taiwan.
Current varieties available for Western
Australian growers are listed in Table 1.
Depending on market demand a premium
may be offered for the Oat 2 variety
Wandering. Consult with your preferred
acquirer to see if a premium will be offered
before planting this variety.
End users often have a preference for a particular variety and growers are advised to
talk to their preferred grain or hay acquirer as to their variety preferences before sowing
an oat crop. Sometimes different end uses also require specific levels of management
and agronomic inputs.
Sowing
Sowing plump seed (certified seed or seed from a paddock with a good fertiliser history)
treated with a seed dressing at the right depth and right spacing is an important first step
towards achieving vigorous and healthy seedlings.
Table 1. Important milling, feed and hay oat varieties
available for Western Australian growers
Oat 1 (milling) Oat 2 (feed) Hay
Carrolup Brusher A Brusher A
Coomallo Dalyup Carrolup
Hotham Euro Kangaroo A
Kojonup A Kalgan Marloo
Mitika A Mitika A Mulgara A
Mortlock Murray Swan
Pallinup A Needilup Tungoo A
Yallara A Potoroo Vasse
Quoll A Wandering A
Swan Winjardie
Toodyay Wintaroo A
Wandering A
Winjardie
Wintaroo A
Yilgarn
Crop establishment
Page 12
Sowing depth
The recommended depth for oat varieties is 3 to 6 cm. This depth is sufficient for the
oat seedlings to emerge through elongation of the mesocotyl and the coleoptile through
the soil. In contrast, wheat and barley seedlings emerge by coleoptile extension only
consequently oats can usually be sown deeper than wheat and barley. In drier seasons
this trait allows oats to be sown relatively deep in an attempt to pursue moisture sufficient
for good germination.
Coleoptile lengths do vary for different varieties as shown for selected varieties in Table
2. Varieties with the longer coleoptile length (such as Winjardie) can generally be sown
slightly deeper than shorter coleoptile length varieties (such as Carrolup).
Using press wheels during sowing will
compress the soil directly above the seed
for even distribution during seeding, and
will sow seed more efficiently in water
repellent soils. Standard tined seeders will
spread seed through a band of 2 to 3 cm
with the occasional seed being left on the
soil surface.
Row spacing
Using press wheels during sowing will compress the soil directly above the seed for even
distribution during seeding, and will sow seed more efficiently in water repellent soils.
Standard tined seeders will spread seed through a band of 2 to 3 cm with the occasional
seed being left on the soil surface.
Plant density
The plant density generally recommended for hay and grain is 240 plants/m2. However,
for hay the plant population can be increased to 320 plants/m2 to help plants compete
better with weeds and to reduce stem thickness, which is desirable in quality export
hay. Oaten hay trials in Western Australia have shown that increasing the number of
established plants increases hay yields in addition to reducing stem thickness.
Higher plant densities also compensate for the lack of tillering experienced in waterlogged
conditions.
If moderate to high grass weed densities are likely, increase the target plant densities
to approximately 400 plants/m2. This will increase crop competitiveness against weeds.
Research has shown that increasing the seeding rates from 240 to 400 plants/m2 reduced
weed biomass by 25 per cent without any effects on grain yield and grain quality.
Higher seeding rates should also be used in the following situations when:
Seedling emergence and establishment are likely to be reduced.
Plant tillering is expected to be low because of a variety or soil condition effects.
Sowing is delayed.
Good rains are likely during the season.
Soil fertility and moisture levels are high.
A dry finish to the season is predicted.
There is a high possibility of an insect infestation that will cause seed mortality.
Where lodging could be a problem, target densities should be reduced marginally. This
encourages the crop to grow thicker stems but not to the extent that it might reduce hay
quality with overly-thick stems.
Table 2. Coleoptile length of selected oat varieties
after germinating in the dark for 12 days at 20°C
Variety Coleoptile size Length (mm)
Carrolup Medium 60 to 69
Dalyup Long 70 to 89
Mortlock Long 70 to 89
Winjardie Very long > 90
Crop establishment
Page 13
Table 3. Amount of seed required (kg/ha) to achieve a desired plant population for some oat
varieties (80 per cent establishment is assumed)
Average grain weight (mg) Target plant populations (plants/m2)
160 240 320
Seeding rate (kg/ha)
33 (e.g. Echidna, Vasse) 66 99 132
35 (e.g. Possum A) 70 105 140
37 (e.g. Carrolup, Kojonup A, Wandering A) 74 111 148
39 (e.g. Dalyup, Swan, Winjardie) 78 117 156
In crops grown on stored soil moisture under rain fed conditions typical of the state, the
population should not be so high that it depletes most of the moisture before the crop
matures and not so low that it leaves moisture unutilised.
Oats for hay can also be sown in a cross fashion (in two directions) to accommodate
more plants which aids in reducing stem thickness and weed population.
Calculating / estimating seeding rates
The number of plants established from a given weight of seeds depends on the size of the
seeds and the percentage of those seeds that are viable and grow into established plants.
Depth of sowing, disease, soil crusting, moisture and other stresses in the seedbed will
affect the number of plants establishing.
Oat varieties differ in their grain weight. The average grain weight of some varieties are
shown in Table 3. To estimate seed weight for those not listed, count and weigh 1000
grains of the graded seed sample. The seed rate can then be calculated by using the
following formula opposite:
For example, for the desired plant population of 240 plants/m2 with an average grain
weight of 40 mg and an expected establishment of 80 per cent, the required seeding
rate is (240 x 40)/80 = 120 kg / ha.
More examples of seed rates calculated on the basis
of target plant populations, grain weight and an
expected 80 per cent seed germination percentage
are shown in Table 3.
Estimating target plant population
Estimating seedling numbers is a way to determine how well the crop has established.
Count the number of plants four to six weeks after seeding at a minimum of 10 randomly
selected sites representing the whole paddock. Place a 1 m long ruler between two rows
and count the number of plants along both sides of the ruler. Use the formula opposite
to estimate the plant population in one square metre
area.
For example, if 1000 plants are counted from 10
sites, and row spacing is 18 cm, the number of plants
per square metre is: 1000 / {10 x (2 x 0.18)} = 278.
Sowing time
Opening rains or seasonal break and the maturity time of the chosen variety dictate when
to sow oats. Sowing time should be matched to the maturity of the chosen variety to
ensure that the plant flowers at its optimum time and reaches its maximum yield potential.
Crops that flower too early may not achieve maximum growth resulting in low yields and
the crop is exposed to the risk of frost damage and weather staining of the grain. Crops
that flower too late may have lower yields and higher screenings due to grain filling
occuring at higher than optimum temperatures and limited soil moisture.
Seeding rate (kg/ha) = {Target plant density
(plants/m2)} x Average grain weight (mg) /
Expected establishment (per cent)
FORMULA
Plant population (plants/m2) = total number of
plants counted / {total metre length x (2 x row
spacing)}
FORMULA
Crop establishment
Page 14
The varieties Needilup, Possum, Swan and Winjardie are more daylight sensitive than
other oat varieties. This means that these varieties may flower at a different time relative
to other varieties in the same maturity group when sown in early May or late June. For
example, Winjardie sown in late April may reach the watery ripe stage 14 days later than
Carrolup. However, when sown in May Winjardie is only 7 days later than Carrolup and
3 days later than Carrolup when sown in late June reaching the watery ripe stage.
It is important to know the relative maturity of hay varieties for hay production, particularly
if the hay enterprise is particularly large. A number of varieties with differing maturities
can be grown which will then increase the optimum cutting/swathing window for quality
and production and subsequent baling. It also reduces the risk of weather damage to
the entire hay enterprise.
For most areas in Western Australia, the ideal time to flower (flowering window) is
September. For areas around and north of the Great Eastern Highway the flowering
window is the whole of September. For the Great Southern the flowering window ranges
from mid-September to early October.
Long season varieties (e.g. Vasse) should be sown first from late April to mid-May. Short
to medium season varieties (e.g. Hotham and Carrolup) should be sown from late May
to mid-June in late June. Table 4 shows the maturity groups of some grain and hay oat
varieties. The maturity group ranking is based on the flowering date of oats when sown
in late May and early June.
Table 4. Maturity groups for some oat grain and hay varieties
Maturity Varieties
group Grain Hay
Early Hotham, Pallinup
Early – Medium Brusher, Wintaroo
Medium Carrolup, Coomallo, Dalyup, Kojonup, Carrolup, Massif, Swan,
Mitika, Quoll, Wandering, Carrolup, Yallara Wandering, Wintaroo
Medium – Late Kangaroo, Winjardie
Late Needilup Vasse
As hay needs to be relatively clean and
weed-free, sowing time may also be
dictated by the need to wait for weeds
and volunteers to germinate to ensure a
good knockdown before sowing.
Research in Western Australia has shown
that delayed sowing causes reductions in
yields of up to 17 kg/ha/day (Figure 1) and
affects the quality of the grain (Figure 2).
Figure 2 represents the effect of seeding
time on quality of grain oats. The values
are the difference between early and late
seeding treatments giving a positive (+)
if early sowing value is higher quality or
negative (-) values if late sowing value is
higher quality. It is apparent that the grain
physical quality declined when sowing
was delayed. Average grain weight (1000
grain weight) decreased in all but one trial
when oats were seeded late. Hectolitre
weight decreased also and screening
(%<2.00 mm) levels increased in 14 out of
4.0
3.0
2.0
1.0
0.0
Grain yield (t/ha)
Calingiri
Beverley
Katanning
Calingiri
Beverley
Katanning
Calingiri
Beverley
Katanning
Site year
Early Sowing Late Sowing
20052004 2006
Figure 1. Interaction of time of sowing and site_year on
average oat grain yield. (LSD <0.05: TOS = 0.45; site_year =
0.18; TOS x site_year = 0.35)
Crop establishment
Page 15
18 trials. Influence on groat content was not very clear whereas protein content increased
while oil content declined with delayed sowing in majority of trials. Also grain colour was
reduced but grain brightness improved in most of the trials due to late sowing.
Early sowing
Sowing as early as possible with a later maturing variety can result in the following for
grain:
The crop will have the opportunity to achieve the highest possible yield (Figure 1).
The grain protein content will be lower (a one-month delay in sowing can increase
protein by 1 per cent) (Figure 2).
For hay:
Foliar diseases will be more severe. So it is important to consider the more disease
resistant varieties.
In good growing conditions the crop will be taller and may lodge.
Sowing early with an early maturing variety increases the risk of cut hay being exposed
to rainfall.
Late sowing
Sowing late in the season with an early maturing variety may lead to the following for
grain:
The crop will be lower yielding but will have higher grain protein because it will flower
and fill the grain later in spring when moisture is likely to be limiting and temperatures
are higher.
For hay:
Foliar diseases, lodging and shedding might be less severe.
Hay quality may be reduced.
Figure 2. Rug plot showing change in quality traits as a
consequence of late sowing (early sowing minus late sowing,
values are +/-). Each point represents one experiment.
Unit difference (normal vs late sowing)
-10.50 -8.00 -5.50 -3.00 -0.50 +2.00 +4.50
Unit difference
(
normal vs late sowin
g
)
-1
0
.5
0
-8
.
00
-
5.5
-3
.
00
-0
.5
0
+2
.
00
+
4.5
0
Fertilisers and plant nutrition
Page 16
Fertilisers and plant nutrition
Raj Malik, Ross Brennan, Blakely Paynter
Oat has traditionally been considered a low input crop and has generally been grown
on paddocks with lower soil fertility. The development of higher yielding grain and hay
varieties combined with greater emphasis on grain and hay quality from both export
and domestic markets means that nutrient management now has to be more carefully
considered when growing oats.
The agricultural areas of Western Australia are dominated by sandy soils. They are
characterised by low amounts of organic matter and a poor ability to retain water and
nutrients. As with wheat and barley crops, oat crops grow poorly without the addition of
nutrients. The major nutrients required for healthy growth are nitrogen (N), phosphorus
(P), potassium (K) and sulphur (S); and the micro-nutrients required for healthy growth
are copper (Cu), manganese (Mn), molybdenum (Mo) and zinc (Zn).
Oat crops, particularly oaten hay, remove significant quantities of all the major nutrients.
It is, therefore, important for growers to use both soil testing and tissue testing to ensure
that the crop nutrient status is adequate for plant growth. Application of nutrients is
required to optimise production either on an annual basis for nutrients like N and P or
less frequently for the micro-nutrients like Cu and Zn. Table 5 gives an estimate of the
quantity of nutrients removed in one tonne of grain and straw. However, these values
can vary markedly with soil type, season and management.
Table 5. Quantity of nutrients removed (kg/ha) in one tonne of product (t/ha)
Nutrients Nutrients lost (kg/ha) in 1 tonne of product
Grain Straw Cereal hay Lucerne
(Soft dough stage)
P 2.5 0.5 2.1 3
K 4 10 12 22
S 3 0.5 1.5 3
Ca 0.3 1 1 14
Mg 1 0.7 1 3
N 20 5 16 28
Lime 0 15 15 60
The continued loss of nutrients from paddocks without replacement becomes particularly
important when the soils are already marginal or deficient in nutrients. The continued
depletion of nutrients, particularly K from soil with adequate amounts will eventually
reduce soil K supply and decrease the productivity and quality of produce. Removing
nutrients from the soil may also reduce the pH of the soil. As the plant material is removed
from the paddock, there is a net export of alkalinity which leaves behind residual hydrogen
ions in the soil to maintain electrical balance. Over the time, as this process is repeated
the soil becomes acidic. Farmnote 97/2001 (Falconer & Bowden 2001) provides further
information on when exported nutrients should be replaced and the implications and
cost for crop production when soil fertility falls below critical levels.
Nitrogen
The importance of N management
Nitrogen is largely responsible for setting up the yield potential of the crop. Nitrogen is
required for tiller development and required by plants to create protein. The N for plant
growth is supplied from both the soil and from N fertiliser application. Nitrogen is taken
up by the oat plant when it is in an inorganic form (as either ammonium or nitrate). In
the soil over 98 per cent of the N is in an organic form which cannot be taken up by the
oat plant until it is mineralised. A large proportion of the oat plants requirement for N is
Fertilisers and plant nutrition
Page 17
supplied by the soil. Where the available N supply from the soil is inadequate for optimum
yield and quality, N fertiliser is required. Soil testing helps estimate the amount of N
already available in the soil. Soil type, cropping history, yield potential and the season
are important factors to consider in N management decisions.
The amount of N fertiliser required to grow a grain or oat hay can be estimated from
fertiliser decision support programs. One such decision support tool is Select Your
Nitrogen. It was developed by the Department of Agriculture and Food Western Australia.
Select Your Nitrogen is a spreadsheet based decision support tool for quantifying N
availability and crop response.
As a rule of thumb, N fertiliser at 40 to 80 kg N /ha has been found ideal for most growing
conditions in WA. The amount of N required will be modified by seasonal conditions
and the oat variety. As dwarf varieties like Kojonup and Wandering have a higher N
requirement, it is suggested that the N application rate used be increased by about 20
per cent above that recommend for a non-dwarf variety like Carrolup. Plant emergence
can be reduced if applying urea at more than 30 kg N /ha is drilled too close to the seed.
Oat hay and grain yield increases (response) to applied N depends on the soil moisture
available during the season. In a dry season there is usually a poor crop response to
applied N due to the reduced rate of mineralisation of granular N fertiliser and possible
lack of soil available water. Depending on the crop yield potential, applying a foliar spray
of N in drier years may be a better option than granular fertilisers. Poor finishes to the
season also reduce crop yield irrespective of how much N is applied.
In wet seasons, leaching of N can occur, particularly in sandy soils. In leaching situations,
the N requirement for oats can be delayed and/or split to reduce the N lost by leaching.
To maximise hay quality, any late N should be applied between tillering (Z25) and stem
elongation (Z31). Applying N too late (later than Z33) causes nitrates to accumulate
in the plant dry matter reducing hay quality. For grain yield, profitable responses to N
application have been found up to 10 weeks after sowing. There is generally little chance
of a profitable yield increase to N fertiliser occurring if the N is applied later than 10 weeks
after seeding.
Tables 6 and 7 provide examples of how N fertiliser can influence the yield and quality
of oats when grown for grain (Table 6) and hay (Table 7). Data are presented from six
experiments, three conducted in 2005 and three conducted in 2006.
Increasing N supply:
may increase hay yield
increases hay greenness
increases stem fibre levels (ADF and NDF)
decreases WSC
may increase IVD and ME slightly
may sometimes lead to high nitrate N levels. High nitrate levels are unacceptable in
many hay markets
interacts with variety for fibre and WSC. Research has suggested that quality of
Kojonup hay is least sensitive and of Wandering is more sensitive to higher applications
of N levels (Figure 3)
method of N application is also important. Research has shown that it is important to
split N, particularly for hay. Figure 4 provides an example of how 3 varieties responded
differently to split N in 2 trials conducted at Katanning and Narrakine in 2007. Varieties
may respond differently to split N. It’s evident that varieties Wintaroo and Wandering
required all the N be applied early at seeding as opposed to Carrolup which required
N to be evenly split between 6 weeks after seeding and at Z31. No variety responded
to the entire N applied later at Z31.The data also suggested a late N may not have any
detrimental effect on grain yield regardless of variety. Further research is required on
methods of N application including Flexi N for oat varieties at a range of locations.
Fertilisers and plant nutrition
Page 18
Table 7. Change in hay yield and hay quality as nitrogen supply is increased from 15 to 80 kg N/ha
at six sites sown in 2005 and 2006
Hay yield Leaf Crude ADF
(t/ha) greenness protein (%)
(SPAD) (%)
N applied (kg N/ha)
Year Rainfall (mm) Site 15 80 15 80 15 80 15 80
2005 210 Highbury 7.9 10.8 40 46 3.2 4.0 23.7 25.2
482 Kojonup 6.5 10.5 42 46 3.2 4.1 26.4 30.5
312 Pingrup 4.8 6.3 39 44 3.9 5.5 22.7 22.4
2006 236 Williams 6.6 7.4 50 50 6.2 8.2 26.3 27.6
303 Boyup Brook 9.6 9.9 46 46 6.0 7.6 29.3 30.0
154 Pingrup 5.6 5.4 45 45 7.5 9.5 23.4 23.6
Average 6.8 8.4 44 46 5.0 6.5 25.3 26.6
LSD (p=0.05) N 0.1 0.8 0.2 0.3
Site year x N 0.7 2.3 0.6 0.8
NDF IVD Est ME WSC
(%) (%) (MJ/kg DM) (%)
N applied (kg N/ha)
Year Rainfall (mm) Site 15 80 15 80 15 80 15 80
2005 210 Highbury 40.6 42.0 61.5 61.9 8.7 8.8 42.0 38.3
482 Kojonup 45.0 50.1 59.5 57.6 8.4 8.2 38.5 32.5
312 Pingrup 39.7 39.4 63.9 65.5 9.1 9.4 41.8 39.8
2006 236 Williams 45.8 48.9 64.3 64.6 9.2 9.3 33.7 28.2
303 Boyup Brook 50.8 52.7 60.9 60.8 8.7 8.7 27.1 22.9
154 Pingrup 45.1 45.6 67.6 69.5 9.7 10.1 28.1 24.8
Average 44.5 46.5 63.0 63.3 9.0 9.1 35.2 31.1
LSD (p=0.05) N 0.3 0.3 0.04 0.5
Site year x N 1.0 0.7 0.1 1.2
Table 6. Change in grain yield and grain quality as nitrogen supply is increased from 15 to 80 kg N/
ha at six sites sown in 2005 and 2006
Grain yield Average grain Hectolitre Screening
(t/ha) wt (mg) wt (kg/hl) (%< 2 mm)
N applied (kg N/ha)
Year Rainfall (mm) Site 15 80 15 80 15 80 15 80
2005 210 Highbury 2.7 3.4 35.8 34.6 58.0 58.2 1.5 1.9
482 Kojonup 3.4 3.7 40.7 41.3 56.3 56.6 1.1 1.0
312 Pingrup 1.9 2.1 33.9 32.8 59.7 59.1 2.6 3.4
2006 236 Williams 1.8 1.9 34.1 33.4 61.1 60.0 4.7 6.8
303 Boyup Brook 3.3 3.3 36.2 35.4 55.3 54.7 3.1 3.9
154 Pingrup 1.8 1.6 31.1 30.2 54.4 53.2 10.0 14.1
Average 2.5 2.7 35.3 34.6 57.5 56.9 3.8 5.2
LSD (p=0.05) N 0.03 0.1 0.1 0.1
Site year x N 0.3 0.9 0.8 0.8
Protein Oil Groat Grain
(%) (%) (%) brightness
(Minolta L)
N applied (kg N/ha)
Year Rainfall (mm) Site 15 80 15 80 15 80 15 80
2005 210 Highbury 8.0 10.4 7.7 7.1 82.9 83.2 61.2 61.4
482 Kojonup 9.9 11.3 7.8 7.5 83.8 85.2 55.6 55.6
312 Pingrup 9.7 12.1 7.8 7.1 86.0 85.9 60.1 59.6
2006 236 Williams 12.6 14.1 5.9 5.6 75.5 75.4 61.0 61.0
303 Boyup Brook 10.4 12.0 6.5 6.2 79.6 79.1 59.8 59.9
154 Pingrup 14.6 16.5 5.6 5.3 82.6 81.2 63.3 63.2
Average 10.9 12.8 6.9 6.5 81.7 81.7 60.2 60.1
LSD (p=0.05) N 0.1 0.1 0.3 NS
Site year x N 0.8 0.2 1.1 NS
Fertilisers and plant nutrition
Page 19
Figure 3. Decline in hay quality of various oat varieties due to higher application of N (data
averaged over six sites sown in year 2005 and 2006). LSD (N x variety, P=0.05) - ADF = 0.68,
NDF = 0.87, WSC = 1.05)
Figure 4. Example of how split N can influence the hay yield of three oat varieties. (E = all N
at seeding; EL = split, 50% at seeding and 50% at Z31; EM = split, 50% at seeding and 50%
at 6 weeks after seeding; L = all N at Z31; M = all N at 6 weeks after seeding; ML = split, 50%
at 6 weeks after seeding and 50% at Z31).
That data are averaged over 2 sites Katanning and Narrakine.
Carrolup
Kojonup
Mitika
Possum
Wandering
Carrolup
Kojonup
Mitika
Possum
Wandering
Carrolup
Kojonup
Mitika
Possum
Wandering
15 N80 N
Varieties
15 N80 N 15 N80 N
0
5
10
15
20
25
30
35
% content
38
40
42
44
46
48
50
52
NDF ADF
0
5
10
15
20
25
30
35
40 WSC
Hay yield (t/ha)
10
9.5
9
8.5
8EELEMLMML
Time of application
CarrolupWandering Wintaroo
Hay yield (t/ha)
4.4
4.15
3.9
3.65
3.4 EELEMLMML
Time of application
Grain yield (t/ha)
80 N15 N
2.8
2.7
2.6
2.5
2.4
200 250 300 350
Plant establishment (/m2)
Screenings % (2.0 mm)
80 N15 N
6.0
5.0
4.0
3.0
200 250 300 350
Plant establishment (/m2)
Nitrogen interaction with
seeding rates
The research has shown that the response
of oat grain yields to seeding rate was
independent of the N application rates
(Figure 5). High seeding rates and high N
fertiliser rates increased screenings but no
other quality parameters (Figure 5).
For hay production, do not apply excessive levels
of N as it may decrease hay quality by increasing
stem fibre levels (ADF and NDF) and decreasing
water soluble carbohydrates. Varieties may differ
in their response to amount and of method of
applied nitrogen.
SUMMARY
Figure 5. Relationship between plant density and applied nitrogen (15 and 80 kg N/ha) on oat
grain yield and screening levels (data averaged across five oat varieties sown at three sites in
each of the 2005 and 2006 seasons).
Fertilisers and plant nutrition
Page 20
Figure 6. Relationship between plant
numbers and applied nitrogen (15 or
80 kg N/ha) on hay yield (t/ha), stem
thickness (mm) and leaf greenness
(SPAD). Data are averaged across five
oat varieties sown at three sites in each
of the 2005 and 2006 seasons.
Increasing the seeding rate will increase oat
grain and hay yields irrespective of N fertiliser
levels. Higher seeding rates will increase grain
screenings and reduce leaf greenness in hay.
However, higher N fertiliser rates will increase
yields.
SUMMARY
Hay yield response to seeding rate was
independent of the level of applied N
(Figure 6).
Leaf greenness was the only aspect of
hay quality that decreased as seeding rate
and N levels increased (Figure 6). At low
levels of N there was a larger drop in upper
canopy leaf greenness as the number of
plants sown increased, compared greater
amount of N applied. Stem thickness of
oats decreased as seeding rate increased
irrespective of N fertiliser (Figure 6).
Nitrogen interaction with
potassium
Trials conducted at at Katanning,
Meckering, Narrogin, Yerecoin, Brookton
and Williams have shown that both N
and K are important to optimize yield and
quality of oat hay and grain. When soil
tests K levels are low (Colwell K soil test
of less than 80 mg/kg) the response of
oat plants to fertiliser N can be affected
by K deficiency. To optimise the response
to fertiliser N, adequate K fertiliser has to
be applied.
The results suggested that both oats hay
and grain yields were governed mainly by
applied N but required at least 70 kg K/
ha to achieve their optimum levels (Figure
5). The hay yield increased by 1.7 t/ha by
applying an extra 65 kg of N (from 15 to
80 kg N/ha) where no K was applied, whist
Hay yield (t/ha)Stem thickness (mm)
Leaf greenness (SPAD)
80 N15 N
9.0
8.5
8.0
7.5
7.0
6.5
6.0
4.9
5.0
5.1
5.2
5.3
5.4
5.5
49
48
47
46
45
44
43
42
41
40
48
200 250 300 350
200 250 300 350
200 250 300 350
Plant establishment (/m2)
at 70 kg applied K the corresponding hay yield increased by 2.1 t/ha. Highest hay yield
was achieved with 80 kg N/ha and 100 kg K/ha. This means that N and K are required
in adequate amounts to achieve maximum economic yield.
Whilst N and K interact to influence hay
yield, they do no interact to influence hay
quality. On K deficient soils, increasing K
(regardless of N supply) reduces NDF and
crude protein and increases WSC of the
hay.
Grain yield increased as combined N and
K fertiliser rates increased (Figure 7). For
example, with no applied K, grain yield
increased by 180 kg/ha by increasing
N application from 15kg to 80 kg/ha,
whereas at 70 kg applied K, the grain yield increased by 377 kg/ha with the additional
65 kg N. At lower N level (15 kg N/ha), there was no grain yield response to added K after
70 kg K/ha. This relationship suggests that it will not be economical to add K without an
adequate amount of N fertiliser.
Whilst N and K interact to influence hay yield, they do no interact to influence hay quality.
On K deficient soils, increasing K (regardless of N supply) reduces NDF and crude protein
and increases WSC of the hay.
The interaction between N x K on hay and grain yield is presented in Figure 7. Under
low N fertiliser (15 kg N/ha), applying 70 kg K/ha increased hay yields by only X t/ha
Fertilisers and plant nutrition
Page 21
Maintaining adequate amount of N and K
nutrition are necessary for optimum grain and
hay yields. High rates of K resulted in better
grain and hay quality.
SUMMARY
and grain yields by only 0.2 t/ha. Under high N fertiliser (80 kg N/ha), applying 70 kg K/
ha increased hay yields by y t/ha and grain yields by 0.4 t/ha. Under low N no further
increases in yield were found with increasing K fertiliser, whereas yields continued to
increase under high N. This suggests that it may not be economical to add K without
adequate amount of N fertiliser.
As with grain yield, N and K can also
interact to influence grain quality. Grain
quality is also affected by combined N
and K fertilisers. Under low N supply,
there is little benefit of K, but with high
N supply, a lack of K can affect quality.
For example grain hectolitre weight was
lower and screenings levels were higher
at high amounts of applied N with insufficient K, as illustrated in Figure 8. Higher rates
of K also improved average grain weight and groat percentage.
Nitrogen deficiency symptoms
Nitrogen deficiency symptoms of oats appear in the early growth stages. Symptoms of N
deficiency become more severe as the oat plant grows. When the crop is young, stems
are short and thin; leaves and stems are pale green. At flowering, N deficient plants are
stunted, have fewer tillers and smaller heads than N adequate plants. At maturity the
crop is multi-coloured with upper leaves pale green and middle leaves yellow to pale
green with red tips. The oldest leaves may have died, turned brown and fallen to the
soil surface. Grain yield is reduced primarily through a reduction in kernels per head and
head density.
Heectolitre wt (kg/hl)
80 N15 N
52.5
52.0
50.5
51.0
51.5
020406080 100 120
K applied (kg/ha) K applied (kg/ha)
%Screenings (<2.0 mm)
2.2
2.7
3.2
3.7
4.2
4.7
5.2
5.7
6.2
020406080 100 120
Hay yield (t/ha)
Grain yield (t/ha)
80 N15 N
9.0
8.5
8.0
7.5
7.0
6.5
6.0
5.5
5.0
4.5 1.9
2.0
2.1
2.2
2.3
2.4
2.5
2.6
02040606080 100 120
K applied (kg/ha) K applied (kg/ha)
0204080 100 120
Figure 8. Increase in hectolitre weight and decrease in screening levels of oat grain due to
potassium in the presence of nitrogen. (Data are averaged across three oat varieties sown
at seven sites grown in 2003 and 2004 seasons, LSD = 0.2 and 0.5 for hectolitre weight and
screenings, respectively).
Figure 7. Interaction between N and K on hay and grain yield (Data are averaged
across three oat varieties sown at seven sites grown in 2003 and 2004 seasons, LSD
= 0.3 and 0.1 for hay and grain yield, respectively).
Page 22 Fertilisers and plant nutrition
Water logging and cereal cyst nematode (CCN) damage can give leaf symptoms similar
to N deficiency.
Phosphorus
Phosphorus is a major nutrient for improved oaten hay and grain production. Phosphorus
isavitalcomponentof adenosine triphosphate (ATP),the ‘energy unit’ of plants. ATP
forms during photosynthesis and is used from the beginning of seedling growth through
to the formation of grain and maturity. Deficiencies result in slow growth, decreased hay
and grain yields, inferior quality and subsequently lost income.
It is suggested that P be applied at crop establishment since an adequate supply is
critical for rapid development. Phosphorus is needed during early growth for plant root
development and elongation, so P fertilisers are drilled with the seed during sowing. An
economic response is unlikely if the application is delayed for more than 10 days after
sowing.
The oat crop response to P will be influenced by the level of Colwell P and the ability of
the soil to retain P (Phosphorous Retention Index). On low P fixing soils (PRI < 2 mL/g,
reactive Fe < 280 mg/kg, PBI < 15), P is held very loosely, making it more available to
plant roots and potentially reducing the amount of P required for maximum economic
yield. On medium and high P fixing soils (PRI 2 to 15 and > 15 mL/g, reactive Fe 280 to
1000 mg/kg and > 1000 mg/kg, respectively) P is held more tightly with a lesser amount
available to plant roots. A better response to applied P is expected where soil Colwell
tests are low. Soil testing is, therefore, required before deciding what rate of P to apply.
Do hay crops require the same amount of P fertiliser as grain crops? Research conducted in
2002 and 2003 suggests that hay and grain crops may differ in their optimum requirement
for P. Hay crops grown on high P fixing soils appear to have a higher requirement
for fertiliser P than grain crops. More research however is required to confirm those
observations.
Do oat varieties differ in their requirements for P fertiliser? In general the research
conducted in 2002 and 2003 suggests that the oat varieties used in those trials (Carrolup,
Dalyup, Hotham and Wandering) had similar requirements for P. One trial on a high P fixing
soil however found differences between varieties. At that site the P requirements for 90%
of maximum grain yield ranged from 16 kg P/ha for Dalyup to 42 kg P/ha for Hotham, with
Carrolup requiring 29 kg P/ha and Wandering 22 kg P/ha. Further research is required on
the P requirement of oat varieties for both hay and grain at a range of locations before
any variety specific changes to P fertiliser management would be suggested.
Phosphorus deficiency
symptoms
Phosphorus deficiency results in
poor seedling establishment and root
development. The deficiency symptoms
are usually only occur if the deficiency is
severe and are more noticeable in young
plants as they have a greater relative
demand for P than more mature plants.
The tips of the old leaves become dark orange-yellow and this colour moves towards the
base, usually along the leaf edges. The affected leaves often have green bases, orange-
yellow mid-sections and bright red or purple tips and the edges of the leaves are rolled
inwards. In severe deficiency, affected areas die and turn red and purple.
Phosphorous is important for oat production.
Addition of P fertiliser can increase both hay
and grain yield, depending on the soil test P. The
optimum P requirement for hay and grain appear
to be different. Oat varieties may differ in their P
requirements.
SUMMARY
Page 23 Fertilisers and plant nutrition
Potassium
Potassium (K) is an important nutrient for oat production. Hay crop remove large amounts
of K. Potassium is required for photosynthesis, transport of sugars, enzyme activation and
controlling water balance within plant cells. Deficiency of K results in poor root growth,
restricted leaf development, fewer grains per head and smaller grain size which affects
yield and quality.
Potassium deficiency is more common on lighter textured soils where there is less clay
and organic matter to retain the K in the root zone. The deeper sands on coastal plains
and peaty sands of south coast are the most prevalent K deficient soils of high rainfall
zone of WA. Potassium deficiency is likely to occur if the soil has less than 80 mg/kg of
K in the topsoil.
Potassium deficiency can reduce the tolerance of plants to environmental stresses, such
as drought, frost and waterlogging, as well as pests and diseases. Potassium deficiency
can reduce straw or stalk length leading to lodging problems.
Crop requirements for K change during the growing season. Potassium uptake is low
when plants are small and increases during late vegetative and flowering stages. Research
in Western Australia has shown that oat yield response to added K depended on the soil
extractable K (Colwell K) and environmental conditions. Adding K had a positive effect
on quality for hay and grain where soil K levels were low to deficient.
Potassium deficiency symptoms progresses slowly and can be costly if not detected in
time. Regular soil and plant analysis and nutrient budgeting can ensure that K deficiency
does not occur. Muriate of potash (KCl) is the cheapest form of K. It is applied by top
dressing either before seeding or up 5 weeks after seeding. If K deficiency is diagnosed
in the soil by Colwell extractable soil test, applying 40 to 80 kg K/ha as muriate of potash
(90 to 180 kg/ha) may give an economic yield increase. Potassium at low rates can be
banded below or with the seed at sowing, with sulphate of potash safer than muriate of
potash. Higher amounts of K drilled with seed can decrease seedling germination, mainly
due to salt effect.
Hay crops remove greater amounts of K (about 10 kg K/t) compared to K losses in grain
of cereals. The removal of nutrients in hay has to be considered when planning fertiliser
requirements for following crops. Practices such as swathing of canola and concentrating
and burning of windrows can have significant effects on the spatial distribution of K across
the paddock. For these reasons growers should use soil test results in conjunction with
plant tissue testing and visual symptoms to determine application rates for paddocks.
Decision support tools such as Nu-Logic (CSBP) and KASM (DAFWA) relate soil test
values and other soil characteristics to yield potential to give recommended K application
rates.
Potassium deficiency symptoms
Potassium is very mobile in plants. In deficient plants K is redistributed to the new growth
and the deficiency symptoms first appear in the older leaves. Older leaves turn pale green
and bronze and yellow areas develop in the mid-section of the leaf between the edge and
mid-vein. These areas quickly extend towards the leaf tip until the top two-thirds of the
leaf is bronze-yellow. Grey-brown spots develop within the bronze-yellow areas. Typically,
the deficient plant develops a three tone appearance with green younger leaves, green
with yellow to bronze colours on the middle leaves and brown older leaves.
Sulphur
Sulphur has an important role in the formation of proteins and is essential for the
production of chlorophyll. Crops that have a high N requirement must have adequate S
to optimise N utilisation and protein synthesis.
Sulphur deficiency in oat crops is rare in WA, mainly because of the widespread use of
superphosphate (11% S). As with N and P, most of the S in the soil is in organic forms.
Soils with low amounts of organic matter are prone to S deficiency. Sulphur in organic
matter must be mineralised to sulphate before being taken up by roots. Sulphate is
Fertilisers and plant nutrition
Page 24
mobile in soils and can be leached out of the rooting zone during winter. Deficiencies
therefore mostly often occur in the wetter years. On duplex soils, deficiency symptoms
may be only temporary as roots grow into the deeper soil layers where more S is available.
Sulphur deficiency is expected to increase in oat crops in the future as more compound
fertilisers containing lower S are used in oat production. Hay production, particularly on
sandy soils, is expected to increase the risk of S deficiency as hay crops remove about
1.5 kg S/ha per tonne of hay.
A soil test value of less than 10 mg/kg in the soil surface (0 to 10 cm) may indicate likely S
deficiency. However, S in the soil frequently increases down the soil profile, so knowledge
of the distribution of S in the soil profile is required. This may involve deeper soil sampling
to know the S supply in the soil. Applying P as superphosphate and compound fertilisers
that applies S at 5 to 10 kg/ha can avoid S deficiency.
Sulfur deficiency symptoms
The youngest leaves of S deficient plants are pale green and then pale yellow across
the whole leaf (no striping). Under severe deficiency the entire plant becomes a lemon-
yellow colour and stems become red.
Micronutrients – zinc, manganese and copper
Micro-nutrients (also called trace elements) are important part of total nutrient management,
particularly in no-till systems. Soil test by the DTPA extractant for micronutrients has not
been adequately developed for oats grown on soils of WA.
Zinc
Zinc is a component of many plant enzymes and essential for healthy plant growth
and leaf formation. Oats are highly susceptible to deficient levels of Zn in the soil. After
the initial recommended application, most micronutrients have a long residual value in
the soil. Therefore, both tissue testing and soil testing, in conjunction, can be used to
determine the need for re-application.
Plant symptoms may help to diagnose Zn
deficiency. However, a tissue test may be
required to diagnose Zn deficiency. Zinc
concentrations in the young leaves of less
than 14 mg/kg indicate that the plant is
Zn deficient.
An initial application of 1 to 2 kg/ha zinc oxide (75 per cent Zn) will correct a deficiency
for many years. A foliage spray of 1 kg/ha zinc sulfate (23 per cent Zn) in 50 to 100 L of
water should be applied as soon as Zn deficiency is detected to prevent grain and hay
yield losses.
Zinc deficiency symptoms
Zinc deficiency causes patchy growth, with plants in poor areas stunted with pale green
leaves and yellow or orange-red tips. Youngest leaves usually remain green, middle and
older leaves turn pale green and pale yellow areas develop between the leaf edge and
mid-vein at the tip. Brown spots occur in the affected areas, increasing in size until the
leaf tip dies, often turning red-brown to black.
With severe deficiency the stem remains very short and youngest leaves have difficulty
emerging fully. The symptoms can be mistaken with that of barley yellow dwarf virus
and severe P deficiency.
If K deficiency is diagnosed by soil analysis,
apply 40 to 80 kg/ha of K in the form of muriate
of potash (90 to 180 kg/ha KCl) near seeding.
SUMMARY
Fertilisers and plant nutrition
Page 25
Manganese
Oats have been found to be highly susceptible to Mn deficiency which can cause
significant yield losses. In severe cases, the crop may die entirely.
Tissue tests and visual symptoms can be used to help diagnose Mn deficiency. Mn
concentrations less than 20 ppm (mg/kg) in whole shoots indicate Mn deficiency.
The concentrations of Mn in tissues vary for different oat varieties (Table 8). The Mn
requirement of different oat varieties requires further research work.
Applying manganese sulphate (25% Mn) as a foliar spray at a rate of 4 kg/ha (1 kg Mn/ha
in 50 to 100 L of water) immediately symptoms appear is usually effective in correcting
a Mn deficiency. However, a repeat spray application of Mn may be necessary a few
weeks after the first foliar spray for complete control of the deficiency.
The application of ammonium sulphate and ammonium nitrate can markedly reduce Mn
deficiency symptoms. Drilling fertilisers enriched with Mn can reduce the risk of crop
damage from Mn deficiency. However, even where an ammonium enriched fertiliser has
been used severely deficient patches may still require a foliar Mn spray.
Manganese deficiency
symptoms
In oats, Mn deficiency produces a
conditioncalled‘greyspeck’ which occurs
in patches. Oats become pale green and
young leaves have spots or lesions of
grey/brown necrotic tissue with orange
margins. These lesions will coalesce under
severe Mn deficient conditions. Plants are
weak, stunted, floppy and pale green-
yellow and appear water-stressed even
when adequate soil moisture is available.
Close examination of the leaf frequently reveal slight interveinal chlorosis. The distinction
between green veins and yellow interveinal areas is poor. Symptoms can be confused
with red leather leaf, which is favoured by prevailing high humidity of high rainfall areas.
Symptoms can also be mistaken for take-all.
Copper
Oats are less susceptible to copper deficiency when compared to wheat and barley.
However, Cu is essential for growth and development. Plants need Cu to produce new
cells and for pollen development (sterile pollen), and hence Cu deficiency severely effects
grain yield. Deficient plants that apparently look healthy can produce shrivelled grain
reducing both grain yield and quality.
Tissue tests, using the youngest emerged leaf can help diagnose Cu deficiency. Tissue
tests with Cu concentrations less than 1.3 mg/kg indicate the plant is severely Cu
deficient. Applying 3 to 9 kg/ha of copper sulphate (25% Cu) with fertiliser at seeding in
areas suspected to be deficient in Cu correct the deficiency. Copper fertiliser has a long
residual in the soil, and a single Cu application at recommended rates can last 20-30
years. Intermittent tissue testing of youngest of oats can maintain Cu at adequate levels.
Copper deficiency symptoms
Copper deficient crops have a patchy appearance with plants in poor areas stunted, pale
green and looking limp and wilted even with ample soil water. Late tillers may develop
at nodes or joints above ground. Young leaves turn pale green while old leaves remain
green. Under conditions of severe deficiency, plants may have leaves which die back
from the tip and twist into curls.
The ears of Cu deficient plantareshrunkenwithgapssuchas‘frostedheads’.Theheads
of Cu decient have poor seed-set from sterile pollen thus resulting in ‘white head’,
similar to the ear heads affected from drought, heat stress and frost.
Table 8. Plant tissue concentrations (mg/kg) in relation to
soil Mn availability. Figures in brackets indicate soil Mn
concentration (mg/kg DTPA extractable Mn).
Variety Mn in a Mn in a
healthy plant deficient plant
Kojonup A 10.4 (1.22) 6.7 (0.58)
Possum A 18.4 (0.72) 7.2 (0.50)
Dalyup 8.3 (0.89) 5.0 (0.51)
Wandering A 10.4 (1.05) 5.1 (0.50)
Mitika A 9.5 (1.2) -
Mortlock 6.4 (0.96) -
Weeds
Page 26
Weeds
Abul Hashem, John Moore
Oats are more competitive with weeds than barley, wheat, canola and pulses when sown
at the recommended seeding rates because of a greater tillering ability and leaf area.
Increasing crop density also improves the competitiveness of oats against weeds.
Cutting hay is a common method to reduce the weed seed bank Effective weed
management for hay crops is essential as weed contamination reduces hay quality.
Contamination by weed plants or weed seeds can cause downgrading or rejection of
export hay as there is a weed contamination limit of 5 per cent. There is also a zero
tolerance to annual ryegrass toxicity (ARGT) and prickly weeds such as doublegees. In
Western Australia, the safe level of ARGT in feed is considered to be 200 to 300 galls
per kilogram of grain or hay. The requirement for export hay is strictly less than one gall
per kilogram. Hay will be rejected for export if there are one or more galls per kilogram
detected.
Pre-seeding weed control is vital as in-crop weed options are limited because oats
are more sensitive to herbicides than other crops. Hotham, for example, is sensitive to
chlorsulfuron and can experience more than 10 per cent yield loss when chlorsulfuron is
applied at recommended rates. Mortlock and Carrolup are also very sensitive to phenoxy
herbicides such as 2,4-D and MCPA.
It is better to slightly delay sowing to spray weeds with a knockdown herbicide than
sowing early and trying to carry out in-crop weed control. If in-crop weed control is
required, spray as soon as the crop is old enough to cope with sprays (before the plant
reaches the growth stage Z32) and while the weeds are as small as possible.
Weed control before sowing
The following herbicides provide a good knockdown of a variety of weeds ranging from
annual ryegrass to capeweed:
• glyphosate e.g.,( Roundup® Powermax)
• paraquat / diquat (e.g., Spray.Seed® 250)
• paraquat (e.g., Gramoxone®)
Theseaboveherbicidescanbe‘spiked’withthefollowingherbicidestoprovideimproved
weed control (note: observe the plantback period stated on labels prior to sowing. Check
labels for appropriate mixing ratios):
• 2,4-D amine
• 2,4-D LVE ester
• carfentrazone-ethyl (e.g., Hammer®)
• clopyralid (e.g., Lontrel®)
• dicamba (e.g., Kamba®, Cadence®)
• diuron
• metosulam (e.g., Eclipse®)
• metsulfuron (e.g., Ally®)
• oxyfluorfen (e.g., Goal®).
Registered herbicides for pre-emergent weed control
• clopyralid (e.g., Lontrel®)
• metolachlor (e.g., metolachlor)
• s-metolachlor (e.g., Dual Gold®)
• oxyfluorfen (e.g., Goal®)
• diuron (e.g., Diuron 900WDG)
Weeds
Page 27
Weeds that can be controlled by pre-emergence herbicides include annual ryegrass,
barley grass, silver grass, capeweed, crassula, doublegee, mustards, toad rush, and
wild radish.
Registered herbicides for post-emergent weed control
Table 9 lists the herbicides that are registered for use in emerged oat crops to control either
grasses or broad-leafed weeds. Weeds that can be controlled at post-emergence include
Table 9. Chemicals used to control grasses, monocot and broad-leafed weeds in oat crops
Active chemical Rate Crop and weed stages
(trade name example)
Grasses and monocot weeds 15 to 25 g/ha Crop: 2 leaf stage to early tillering (see
chlorsulfuron 750 g/kg (e.g. Glean®) label for Mortlock oats).
Weed: No later than 3 leaf stage for
annual ryegrass.
Broad-leafed weeds
bromoxynil 200 g/L (e.g. Bromicide®) 1.4 to 2.1 L/ha Crop: From 3 leaf to jointing.
bromoxynil/dicamba/MCPA 0.75 to 1.4 L/ha Crop: From 3 leaf to jointing.
140/40/280 g/L
(e.g. Broadside®)
bromoxynil/MCPA 200/200 g/L 0.75 to 2.0 L/ha Crop: From 3 leaf to jointing.
(e.g. Buctril® MA)
carfentrazone-ethyl 240 g/L 65 to 100 g/ha Crop: 3 leaf to mid-tillering. Add 500
(e.g. Affinity®) mL/ha MCPA amine for certain weeds.
See label.
chlorsulfuron 750 g/kg 15 to 25 g/ha Crop: From the 2 leaf stage.
(e.g. Glean®) Weed: No later than 3 leaf for ryegrass.
clopyralid 750 g/L (e.g. Lontrel® 750) 60 to 120 g/ha Crop: 2 leaf to jointing.
dicamba 700 g/kg 115 g /ha (add 7 g/ha Eclipse
®
Crop: From 3 leaf to early tillering.
(e.g. Cadence®) for some weeds). 200 g/ha Crop: From 5 leaf to early tillering.
(MCPA, 2,4-D or Eclipse® Check label carefully for mixture and
additions may be needed) oil rates.
diflufenican/MCPA 25/250 g/L 0.25 to .75 L/ha Crop: From 5 leaf to late tillering.
(e.g. Tigrex®)
diuron 500 g/L 300 mL/ha [+ 400 mL/ha MCPA Crop: 3 to 4 leaf stage, no later than
amine (500 g/L)] 6 weeks after sowing.
400 mL/ha [+ 500 mL/ha MCPA Crop: 4 to 5 leaf stage, no later than
amine (500 g/L)] 6 weeks after sowing.
500 mL/ha [+ 250 mL/ha 2,4-D Crop: 4 to 6 leaf stage, no later than
amine (500 g/L)] 6 weeks after sowing.
diuron 900 g/ha DF 200 g / ha [+ 400 mL/ha MCPA Crop: From 3 to 5 leaf stage on.
amine (500 g/L)]
280 g/ha [+ 250 mL/ha 2,4-D Crop: From 4 to 6 leaf stage on.
amine (500 g/L)]
flumetsulam 800 g/kg 25 g/ha. Add 100 mL/ha diuron Crop: 3 leaf to jointing. Add wetter.
(e.g. Broadstrike®) for capeweed.
metosulam 714 g/kg 5 to 7 g/ha Crop: 2 leaf to jointing.
(e.g. Eclipse®) Add spraying oil.
MCPA amine 500 g/L 0.9 to 2.0 L/ha Crop: From 5 leaf to flag leaf
emergence.
MCPA low volatile ester 500 g/L 0.5 to 1.6 L/ha Crop: 3 leaf to flag emergence.
MCPA/Picolinafen 500/50 g/L 250 to 500 mL/ha Crop: 3 to 5 leaf.
(e.g. Paragon®)
triasulfuron 750 g/kg 10 to 15 g/ha Crop: 3 leaf to tillering.
(e.g. Logran®) Weed: Wild radish 2 to 6 leaf.
Add a spraying oil.
2,4-D amine 300 g/L 1.1 to 3.3 L/ha Crop: 5 leaf to jointing.
(e.g. Surpass® 300)
2,4-D amine 475 g/L 0.8 to 1.6 L/ha Crop: From 5 leaf to flag leaf
emergence.
2,4-D amine 625 g/kg 0.64 to 1.3 g/ha Crop: From tillering to boot stage.
(e.g. Amicide® 625) Apply after 6 leaf stage in Mortlock
oats.
Weeds
Page 28
annual ryegrass, cape tulip, capeweed, clover, dock (seedlings), Guildford grass, corn
gromwell, doublegee, flatweed, fumitory, London rockets, lupins (volunteer), mallows,
matricaria, medics, mustards, Paterson curse, prickly lettuce, rough poppy, turnip weed,
saffron thistle, skeleton weed, sow thistle, wild turnip, wireweed, and yellow burrweed.
Further information about variety resistance to herbicides can be found on the oat web
pages (<www.agric.wa.gov.au>). Herbicide recommendations can be found in the latest
Cereal Spray Charts : at DAFWA offices in e-weed and Planfarm Herbicide Guide. E-weed
is a free newsletter service from DAFWA providing information on weed control issues
throughout the growing season.
Integrated weed management
Preventing weeds from entering or establishing in a paddock is the best method of weed
management. This can be achieved by non-chemical methods such as:
• use weed-free seed. Ask for a seed analysis report
• clean machinery when moving between paddocks on farms
• graze weeds with sheep or cattle
• cut for silage or hay
• use weed-free feed
• increase seeding rates to maximise crop/weed competition
• use chaff carts to collect weed seeds at harvest
• use Harrington seed destructor at harvest time in grain crops
Diseases
Page 29
Figure 9. Oat leaves infected by Septoria avenae blotch (Photo: Raj Malik, DAFWA).
Diseases
Dominie Wright, Geoff Thomas, KithsiriJayasena
Foliar diseases
The major foliar diseases of oats in Western Australia are septoria blotch, leaf rust,
stem rust and barley yellow dwarf virus. Other minor diseases include ring spot and the
bacterial disease stripe blight. All of these diseases have the ability to reduce the yield
and quality of hay and grain in conditions favourable for disease development. Oat crops
should be actively monitored for these diseases.
When diagnosing oat diseases, it is important to look at the big picture and assess overall
what is happening in the paddock.
Disease development depends on:
• presence and abundance of the pathogen (green bridge, oat stubble, infected seed).
• susceptibility of the oat variety to the disease (varieties can have different levels of
resistance to different diseases).
• suitable environmental conditions (high rainfall generally favours foliar diseases).
Septoria avenae blotch
Septoria blotch is the most common oat disease in Western Australia. This disease is
caused by the fungus Phaeosphaeria avenaria (asexual stage: Stagonospora (formerly
Septoria) avenae). The disease is carried between seasons on infected stubble.
The fungus infects leaves, leaf sheaths and stems and under high disease pressure may
also infect heads. Infected leaves have mottled light to dark brown-purple roughly circular
blotches, with dark brown centres that gradually enlarge and coalesce to cover most of
the leaf as the infection becomes more severe (Figure 9).
Diseases
Page 30
Similar lesions occur on the leaf sheath and when severe these lesions can extend
into the stem causing death and blackening which may lead to lodging. The fungus
sometimes causes a dark discolouration of the grain when unseasonably late rain occurs.
Septoria avenae blotch can cause up to 50 per cent yield loss in extreme cases but losses
of around 10 per cent are more common in high rainfall areas.
The disease is stubble-borne, therefore greatest disease risk is associated with
continuous oat crops. Rotating crops and sowing oats following a non-host will reduce
the occurrence of septoria. Burning or incorporating stubble prior to sowing will reduce
risk of early infection in continuous oat paddocks. Tall or slow maturing oats are less
likely to be affected compared to dwarf or fast maturing varieties. Varieties differ in their
resistance to this disease. Sow more resistant varieties in high disease risk paddocks.
Foliar fungicides are registered for septoria suppression and can provide some protection
of yield and quality of grain or hay.
Leaf rust
Leaf rust or crown rust is caused by the fungus Puccinia coronata f.sp. avenae. Round
to oblong pustules (lesions) that are orange to yellow in colour develop primarily on
the leaves but occasionally on leaf sheathes and heads of infected plants (Figure 10).
The powdery spore masses in the pustules are readily dislodged and are spread by
wind, disease can multiply rapidly with
favourable conditions or in a susceptible
host (Figure 11 Leaf rust spore cloud in
oats). As they age, the pustules then turn
black and lose the powdery spore masses.
Leaf rust is a green bridge disease; it
requires a living host to survive between
seasons. Disease risk is highest in seasons
following wet summer / autumn which
will favour survival of rust inoculum on
volunteer hosts, and wild oats. Grazing,
spraying or tilling to control volunteer oats
over summer may help to reduce leaf
rust but the effect can be limited by the
abundance of wild oats that also act as
Figure 10. Leaf rust in oats (Photo: Pamela Zwer, SARDI).
Figure 11. Leaf rust spore cloud in oats
(Photo: Rob Loughman, DAFWA).
Diseases
Page 31
a green bridge. Variety resistance is very
effective therefore avoid planting highly
susceptible oat varieties in rust-prone
areas or in the presence of a green bridge.
Foliar fungicides are registered for leaf
rust management however; ensure that
withholding periods for both hay and grain
are considered in timing of application.
Stem rust
Stem rust is caused by the fungus
Puccinia graminis f.sp. avenae and is one
of the most severe diseases of oats. Its
life cycle and management is similar to
leaf rust. Affected plants have oval or
elongated reddish-brown pustules mainly
on their stems but also on leaves and
heads (Figure 12). The pustules are larger
than those of leaf rust. Lesions produce
masses of powdery spores which can
dislodge readily and are spread by wind. Stem rust is favoured by warm moist weather;
infection can increase rapidly in wet spring conditions.
Similar to leaf rust, variety resistance can effectively reduce rust development, avoid
planting highly susceptible varieties in rust-prone areas or in seasons with high rust risk.
Before sowing oats, control volunteer weeds and plants that may act as a green bridge
for the diseases over summer. Foliar fungicides are registered for stem rust in oats;
although control can be difficult, withholding periods need to be considered in timing of
application.
Virus Diseases
Roger Jones
Barley yellow dwarf virus
Barley yellow dwarf virus (BYDV) is
widespread in high rainfall areas of the
state. It infects cereals and grasses. The
virus survives between cropping seasons
in grasses or volunteer cereals which
persist outside the growing season, acting
as a green bridge. Infection is spread from
grass reservoirs and volunteer cereals
to crops through the migration of cereal
and grass aphids, especially the oat
aphid, Rhopalosiphum padi. Due to the
role of aphids in establishing infection,
BYDV is always more severe following
wet summers when volunteer hosts are
abundant and substantial aphid build-up
and BYDV spread has occurred prior to
sowing.
Plants infected with BYDV have yellow-
brown or orange-brown discolouration near the leaf tip, especially on lower leaves. The
discolouration spreads until most of the leaf is affected and appears red-brown. Later
it changes to a crimson-pink (Figure 13). The distribution of infected plants across the
paddock is normally patchy but occasionally the whole crop may show symptoms.
Figure 12. Stem Rust in oats (Photo: John Sydenham,
DAFWA).
Figure 13. Barley Yellow Dwarf Virus in oats
(Photo: Pamela Zwer, SARDI).
Diseases
Page 32
Infection at all growth stages can be damaging, however infection occurring early in
the crops growth has greatest potential for crop damage. Oats infected with BYDV as
seedlings show additional symptoms of severe stunting, increased tillering and floret
abortion.
To reduce risk of BYDV infection, sow more resistant oat varieties. The planting date can
also be adjusted so that young crops aren’t exposed to periods of high aphid numbers;
however, the benefit of this strategy needs to be weighed up against yield penalties from
delayed sowing.
Once aphids contract the virus they remain infected for the rest of their lives. Hence in
high risk seasons it is critical to prevent the spread of the virus in the first eight to ten
weeks after crop emergence, when there is the greatest potential for crop damage, by
applying insecticides to eradicate aphids. In high risk aphid years (with a summer/autumn
green bridge or in disease prone regions), anti-feeding insecticides (alpha-cypermethrin)
should be applied at 3 and 7 weeks after emergence regardless of whether aphids can
be seen on the plants. A web based forecasting system is available which shows which
localities need these sprays and which don’t in any particular year. It is recommended
that you reassess your disease risk at seeding by viewing the crop disease forecasts on
the DAFWA website at www.agric.wa.gov.au/cropdisease.
Bacterial blights
There are two types of bacterial disease which infect oat foliage; halo and stripe blight.
Halo blight (Pseudomonas syringae pv. coronafaciens) causes light green-coloured, oval-
shaped spots up to 10 mm surrounded by a pale halo with a water-soaked appearance.
Spots turn brown and fuse together into blotches (Figure 14).
Stripe blight (Pseudomonas syringae pv. striafaciens) forms long, red-brown stripes on
leaves during winter (Figure 15), which join into blotches that cause leaf collapse (blight).
It is easy to confuse this disease with Septoria avenae blotch.
Stripe blight is most common in continuous oaten hay crops and is prevalent with
extended periods of moist weather which facilitates splash of bacteria and provides
suitable conditions for infection. The disease is favoured when crop density is high and
there has been a high input of nitrogen making the plants soft. As the growing season
progresses, plants generally grow away from this disease. Warm dry spring conditions
will rapidly reduce spread of this disease. Unless infection is very severe, yield losses
are not known to be significant. The disease will lower the quality of the hay.
There is no chemical control for this disease (fungicides are not registered or effective
against bacterial diseases). As a management tool avoid sowing into infected stubbles
and burn or incorporate stubble if the problem is widespread. The disease can be seed
borne, do not re-sow seed from infected crops. To prevent disease spread, paddock
hygiene is important. Therefore, paddock operations should be avoided when leaves
are wet.
Ring spot
Ring spot is a common disease which is widespread throughout agricultural areas. The
fungus infects leaves and occasionally leaf sheaths causing small ring spots with dark
rims and bleached tan centres. It has a wide host range and produces similar symptoms
on a range of other cereals and grass weeds. Fungus-infested stubble produces spores
which spread to nearby plants; spores produced on infected leaves do not spread the
disease to other leaves. The disease is most common where grass weeds have been
common in the previous season. It is not known to reduce yields and no direct control
measures are available.
Diseases
Page 33
Figure 14. Halo blight in oats (Photo: Raj Malik,
DAFWA).
Figure 15. Strip blight in oats (Photo: Rob
Loughman, DAFWA).
Loose and covered smut
Loose smut (Ustilago avenae) and covered smut (Ustilago hordei) of oats are seed-
borne diseases with similar symptoms which are difficult to distinguish in the field.
Both diseases are managed in the same way. In affected plants each spikelet is
transformed into a mass of dark brown to black spores which is at first contained
within a fine membrane. After head emergence, this membrane bursts releasing the
spores to contaminate healthy heads, leaving a bare stalk or rachis on the infected
plant. Spores are carried on infected seeds between seasons. After sowing, spores
on the seed surface germinate and infect the emerging seedling, growing without
symptoms within the plant and infecting the developing head completing the disease
cycle. These diseases are well-managed by regular application of fungicide seed
dressing and replacement of contaminated seed stocks.
Diseases
Page 34
Chemical control of foliar diseases
Despite the effort to improve the resistance of oat varieties to leaf diseases, there is
seldom complete resistance or varieties may not have a complete suite of resistance
to all diseases. Therefore agronomic solutions must be used to reduce the impact of
leaf diseases. Fungicide applications are becoming an increasingly important part of
disease control strategies. However, currently in Western Australia there are limited
control options available for oats for use as foliar sprays in oat crops. There are only two
fungicide active ingredients registered for use as foliar sprays in oat crops: propiconazole
and tebuconazole which control leaf and stem rusts. Only propiconazole is registered
to suppress septoria.
Root and crown diseases
Root and crown diseases such as rhizoctonia bare patch (Rhizoctonia solani,), take-
all (Gaeumannomyces graminis var. avenae) and Fusarium crown rot (Fusarium
pseudograminearum, Fusarium culmorum) frequently occur in Western Australian
cropping systems. These diseases are often harder to detect and diagnose than foliar
diseases, above ground symptoms are often indistinct. Lack of vigour or patches in
crops are a common symptom of these diseases. In many cases disease symptoms can
be confused with nutrient deficiencies, herbicide damage or soil constraints. However,
these diseases must be identified correctly to enable appropriate control measures to
be implemented.
Disease symptoms on roots are usually distinctive and when combined with paddock
symptoms, accurate diagnosis can be achieved. The potential for damage by several key
root and crown diseases can be tested by a soil test. The Predicta B soil test provides an
analysis of soil inoculum levels by measuring the level of fungal DNA of pathogens such
as rhizoctonia, take-all, cereal cyst nematode, root lesion nematodes (only P. neglectus
and P. thornei), stem nematode and crown rot.
Rhizoctonia bare patch
Rhizoctonia bare patch has a wide host range and attacks most crop, pasture and weed
species common in WA farming systems. Above ground symptoms appear as roughly
circular patches with distinct edges which become apparent 3-4 weeks after sowing. The
bare patches can vary in size from less than half a metre up to several metres across.
Roots of affected plants are short with brown, pinched ends (spear tips). Plants within
patches may have a purple tinge to their leaves. Yield loss is usually proportional to the
area of paddock affected by patches.
Deep cultivation at sowing with a narrow tine below seed or deep ripping immediately
prior to sowing is the most effective methods of reducing damage caused by this disease.
Ensuring good crop growth through adequate plant nutrition and avoiding herbicide
damage to roots will reduce the impact of this disease. Fungicide seed dressings are
registered for suppression of this disease and these should be used in conjunction with
other control strategies. Crop rotation and variety resistance are do not affect bare patch.
Fusarium crown rot
Crown rot is a fungal disease which survives between seasons on infected stem and crown
residues in soil. Infection in crops is usually first seen after flowering when whiteheads
develop. Single tillers, whole plants or groups of plants can be affected. The lower stem
of affected plants has a honey brown to dark brown discolouration at the stem base.
Moisture stress after flowering exacerbates the development of whiteheads in infected
crops. Oats are less susceptible than wheat and often no symptoms are seen, particularly
in hay crops, although oats can build up disease levels for subsequent wheat crops.
Diseases
Page 35
Take-all
Oats are not susceptible to the wheat take-all fungus. There is an oat form of take-all
which can cause some damage to oat crops, although it does not commonly cause
significant levels of damage. The characteristic symptoms of Take-all are a black root
rot (blackening both the surface and the centre of the root), associated with a blackening
around the base of the stem and subsequent premature ripening of plants causing
whiteheads in severely affected plants.
Crop rotation is the main control for take-all. A one-year break from oat, wheat or grass
hosts is usually enough to reduce inoculum.
Further detailed information on root and crown diseases is available in DAFWA Bulletin
4732: Root disease under intensive cereal production systems.
Nematodes
Vivien Vanstone
Nematodes are common soil pests that feed on the roots of a wide range of crop plants in
all agricultural areas of Western Australia, irrespective of soil type and rainfall. Nematodes
multiply on susceptible hosts. Consequently, as nematode populations increase, crop
production is limited. Cereal yield losses due to nematodes in Western Australia are in
the order of 5 to 25 per cent per annum, but much higher losses to individual crops have
been recorded.
When roots are damaged by nematodes, water and nutrient uptake are less efficient, and
plants are also less able to tolerate other
stresses such as drought. With adequate
soil nutrition and moisture, particularly in
spring, damaged roots may be able to
extract sufficient nutrients to grow and
finish well. Plants affected by nematodes
can be more prone to attack by fungi that
cause leaf and root disease.
In-field diagnosis of nematodes is not
easy, as above-ground symptoms of
infection are difficult to detect. Plants
may show a combination of indistinctive
symptoms, all of which can be confused
with, or exacerbated by, nutrient deficiencies:
• unevengrowthandyellowing;
• stuntinganddecreasedtillering;
• wiltingunderwaterstress.
Nematodes are usually distributed unevenly across a paddock,
resulting in irregular growth or patchiness. Laboratory testing
of plants or soil is often necessary to determine the numbers
and type(s) of nematodes present. Nematodes are microscopic
(less than 1 mm in length) so cannot be seen with the naked
eye (Figure 16).
Cereal cyst nematode
The cereal cyst nematode (Heterodera avenae) can cause
severe damage in areas where continuous cereal cropping is
favoured. In Western Australia, cereal cyst nematode (CCN)
is reported frequently from the Northern Agricultural Region around Geraldton and from
the Central Agricultural Region but it can occur in any area.
CCN only infects cereals and other grasses (particularly wild oat).
Figure 16. Microscopic plant parasitic
nematode (Photo: Sean Kelly DAFWA)
Figure 17. The female
nematodes can be
seen as pinhead-sized
immature cysts on the
root surface (Photo:
Vivien Vanstone DAFWA)
Diseases
Page 36
In infected paddocks, the female nematodes invade the plant roots in autumn. As the
females feed and develop within the roots, their bodies swell and erupt through the root
surface. They can then be seen as white, spherical bodies about the size of a pinhead
on the root surface (Figure 17). At this stage, the female nematodes each contain several
hundred developing eggs.
The cysts turn brown and remain in the soil over summer, where the eggs will hatch at
the start of the next season. CCN needs a combination of moist and cool conditions
to hatch. However, only 70 to 80 per cent of these eggs hatch each season, so some
will remain in the soil for following seasons, even where no hosts are available. For this
reason, it can take several years for high CCN populations to be reduced below levels
which are yield limiting.
Symptoms
Above-ground symptoms can be
indistinct, consisting of patchy and uneven
growth. Plants can also appear stunted,
unthrifty and yellowed. Development of
the whole root system is retarded. The
roots of oats will appear ‘swollen’ and
‘ropey’(Figure18).
With heavy infestation, CCN will cause
distinctive patches of yellowed growth
(Figure 19). These patches can increase
in size and severity with successive cereal
crops.
Figure 18. Cereal cyst nematode causes the
roots of oats to be swollen and stunted (Photo:
Vivien Vanstone DAFWA)
Figure 19a. Cereal cyst nematode causes
yellowed patches in the crop (Photo: Vivien
Vanstone DAFWA)
Figure 19b. Plants are stunted and yellow
(Photo: Vivien Vanstone DAFWA)
Management strategies
Variety selection. Oat varieties differ in their ability to host nematodes. Resistant varieties
act as excellent break crops which limit nematode multiplication, while susceptible
varieties increase the severity of the disease. However, varieties also differ in their ability
to develop normally and produce hay in the presence of the nematode: oat varieties range
from moderately tolerant to very intolerant. Tolerant varieties will develop normally in
the presence of high nematode populations but in the same situation intolerant varieties
would have poor growth or could even die (Figure 20). Therefore, if nematodes are a
problem it is advisable to select a variety with both resistance and tolerance. Oats can
be very sensitive to CCN, so only a low level of nematodes can cause significant damage
to an intolerant variety.
Rotations of legume crops, canola or grass-free pastures with cereals are effective.
Since CCN can only infect cereals and other grasses, rotations incorporating non-cereals
and good control of grass weeds are an effective break. In infected areas, do not grow
more than two consecutive cereal crops following a non-host break crop. However,
Diseases
Page 37
Figure 20a. Growth of tolerant (left) and
intolerant (right) oat varieties in response to
cereal cyst nematode (Photo: Vivien Vanstone
DAFWA)
Figure 21. P. penetrans can cause significant
root damage to oats (Photo: Vivien Vanstone
DAFWA)
Figure 20b. Growth of tolerant (left) and
intolerant (right) oat varieties in response to
cereal cyst nematode (Photo: Vivien Vanstone
DAFWA)
severe soil infestations may require more than one year of a non-host crop to reduce
CCN below yield limiting levels.
Plant clean break crops. Control susceptible cereal volunteers and grasses (particularly
wild oat) in non-host phases of rotations.
Use soil testing to monitor nematode numbers and maintain low levels with rotations.
Chemical treatments for nematode control in cereal crops are not currently available.
These chemicals are expensive and highly toxic to humans.
Cultivation is NOT an effective control
option. This spreads the nematodes
around the paddock and distributes them
throughout the soil profile making the
problem worse.
Root lesion nematode
Root lesion nematode (Pratylenchus
species) inhabits soil and feeds on the
roots of plants. Several damaging species
of Pratylenchus occur in cropping areas of
Western Australia: Pratylenchus neglectus,
P. teres, P. penetrans and P. thornei.
Population densities of all root lesion
nematode (RLN) species will increase
under intensive cereal production. These
nematodes occur across the entire wheatbelt.
At least 60 per cent of Western Australia’s cropping paddocks are infested with one or
more species of RLN, and about 40 per cent of these are at levels which may cause yield
losses in the order of 5 to 25 per cent. There have been individual cases of losses as
great as 40 per cent. In Western Australia, P. neglectus is the most commonly identified
species (detected in 40 per cent of paddocks), followed by P. teres (detected in 10 per
cent of paddocks). P. penetrans has been identified in some crops, including oat,
Diseases
Page 38
where it can cause significant root damage (Figure 21). P. thornei is rare in Western
Australia. More than one species of RLN can occur in a single paddock. All species of
RLN cause identical root symptoms.
For nematode diseases, particularly RLN, the resistance of a crop species or variety is
determined by the plant’s ability to inhibit or support nematode reproduction. Resistant
varieties can be used to reduce the nematode population over one or more seasons.
However, resistant crops will not eliminate RLN and will still support low nematode levels.
For this reason, the nematode population can quickly increase again when a susceptible
crop is sown.
Symptoms
Above-ground symptoms of nematode infection are often indistinct and difficult to
identify. Affected plants are stunted and tiller poorly, and may wilt despite moist soil.
Crops will appear patchy with uneven growth (Figures 22 and 23). Roots may have
indistinct brown lesions or, more often, generalised root browning (Figure 24). When
roots are infested with high numbers of RLN, they are thin and poorly branched. Lateral
root branches are reduced in both length and number. Sections of the root system may
appear dead, with the crown roots often less affected than the primary roots.
Figure 22. Root lesion nematodes cause
patchy and uneven crop growth (Photo: Vivien
Vanstone DAFWA)
Figure 24. Root lesion nematode causes
discolouration of cereal roots, combined with
reduction in root branching (Photo: Vivien
Vanstone DAFWA)
Figure 25. A healthy cereal root
system will produce a large mass of
both crown and primary roots (Photo:
Vivien Vanstone DAFWA)
Figure 23. Root lesion nematodes cause
stunting and reduced tillering of cereal plants
(Photo: Vivien Vanstone DAFWA)
Diseases
Page 39
Management strategies
Root lesion nematode can be managed with rotations and other cultural practices
but cannot be eradicated. The first step towards effective management of nematode
diseases is correct identification of the species present. Extraction and identification of
nematodes needs to be carried out in a laboratory to confirm the RLN species present
and their population density.
Rotations that include resistant crops in the sequence are the most effective means
of reducing the number of RLN in soil, or preventing its build-up. Rotations need to be
tailored to the predominant RLN species present. To maintain low nematode population
densities, avoid continuous cropping with susceptible cereal crops. Crops resistant to
P. neglectus include field pea, faba bean, narrow-leafed lupin, lentil, rye and triticale.
Use resistant varieties. Most oat varieties are Moderately Resistant to P. neglectus.
Oats is, however, more susceptible to P. penetrans. Further information can be found in
annual DAFWA and SARDI variety and disease guides.
Focus weed control on controlling susceptible weeds (particularly wild oat, barley grass,
brome grass and wild radish) and susceptible volunteers (especially cereals) to reduce
RLN build-up and carryover.
Pesticides for nematode control in cereal crops are not currently available. These
chemicals are expensive and highly toxic to humans.
Soil and plant testing services
To determine whether a fungal or nematode root disease is affecting a cereal crop, first
look at the distribution of symptomatic plants throughout the whole crop. Next, carefully
dig up samples of apparently diseased as well as healthy plants. Thoroughly wash the
soil from the roots and examine them for any indicative symptoms.
Suspected root disease or nematode problems in-crop can be confirmed by laboratory
analysis of soil and/or roots. For patch diseases, sample from the edge of the patch
rather than the centre. Do not send washed plants to the laboratory. Follow sampling
guidelines at http://www.agric.wa.gov.au/PC_90018.html?s=709641941.
Growing season tests are carried out on affected plants and associated soil. Although
little can be done during the growing season to correct a fungal or nematode root disease,
it is important to identify the cause of the problem so that decisions on appropriate
management strategies can be taken leading up to and during the following seasons.
Test kits are available from AGWEST Plant Laboratories and participating distributors.
To obtain submission forms and full sampling instructions, contact your local DAFWA
office. Information can also be found at http://www.agric.wa.gov.au/PC_90018.
html?s=709641941 or by phoning 08 9368 3721 or emailing agwestplantlabs@agric.
wa.gov.au.
Pre-season assessment. The risk of root diseases being present in a paddock at a yield
limiting level next season can be determined by paddock history, paddock monitoring
in spring or soil tests. A review of paddock history will identify the diseases likely to
be present in each paddock. The level of disease likely to develop can be determined
by digging up plants in spring from areas of poor growth and examining the roots for
symptoms. An informed decision can be made about the future use of each paddock
based on the presence or absence of a disease and the conduciveness of the current
season and crop to further develop that disease. Pre-season soil tests can be used where
the paddock history is not adequate for planning future use. Soil tests are conducted
on representative soil samples. PreDicta-B uses DNA assessment to determine the
root diseases or nematode species present, and the likely risk of crop damage. Test
kits are available through accredited agronomists and re-sellers, by contacting alan.
mckay@sa.gov.au Ph 08 8303 9375 or at http://www.sardi.sa.gov.au/pestsdiseases/
diagnostic_service/predicta_b.
Insect and allied pests of oats
Page 40
Insect and allied pests of oats
Svetlana Micic, Peter Mangano, Chris Newman
Field pests
A vigorously growing oat crop with adequate plant densities (at least 240 plants per
square metre for an oat crop; 320 plants per square metre for a hay crop) is able to
withstand considerable pest damage with little yield loss. Where sowing depth has been
too deep or crops are moisture stressed pest damage is greater.
Oat crops should be checked regularly to enable control measures to be taken early and
prevent excessive damage especially at the seedling stage.
It is important to correctly identify the pest causing the damage so appropriate control
measures may then be taken. To assist in this process, the appearance and type of
damage caused by caterpillars, lucerne fleas, mites, slugs, snails, aphids, earwigs and
beetles (referred to as invertebrates) is described and their management is discussed.
A key to the damage cause by major pests to oats can be found on next page.
Descriptions of pests, their thresholds and control measures can be found in Table 10.
A table of registered insecticides can be found in Table 11.
For pests not covered by this publication, refer to your local Department of Agriculture
and Food Office for advice.
Chemical control
Routine spraying without monitoring pest numbers may increase the likelihood of insects
developing resistance to insecticides. Consider spraying, only if there is economic
damage occurring to your crop.
Prior to spraying your crop, consider the amount of damage occurring. A good idea is
to consider the suggested thresholds in Table 10.
A good way to find out the extent of insect damage is to monitor a number of random sites
within a paddock. The more sample sites the better. Pests
are not always uniformly distributed in a crop. Sampling
only one or two sites may give a misleading impression
of pest density.
Table 11 shows the rates of insecticides that are registered
for use in oats against common pests .
Vagrant invertebrates in harvested
grain and hay
Vagrant invertebrates are those that are incidentally
harvested with the grain. They do not damage grain.
However, there is a zero tolerance to invertebrates in
export hay.
Most common vagrant invertebrates
One of the most common contaminants of cereal grain is
the bronzed field beetle (Adelium brevicorne).
Other common vagrant invertebrates include: predatory
beetles, vegetable beetles, snails, weevils, grasshoppers,
earwigs and ladybeetles.
Bronzed field beetle
Insect and allied pests of oats
Page 41
Usually found
close to damage
near plants
Snails Slugs European
earwigs
Easily found
under dead
plant matter,
rocks
Crop damage to seedlings
Chewed above ground
Whole plants or
parts of leaves eaten
Irregular pieces or
shredded leaves
Leaves chewed, some plants
cut off at ground level
Root System Chewed
YES
YESYES NONO
NO
Large easy to
see mites Small black mites
Portions of plant material
protruding from tunnel
C- shaped grubs present
in soil
Holes in leaves
usually with white film
Cotyledons with
bleached patches on
leaves
Poor seedling growth
- stunted or dying
No chewing evident
Check for
aphids under
leaves
Webworm Cutworm Lucerne flea Balaustium mite Earthmites Cockchafer Desiantha larvae
Are resticted to
heavier soils
Found under
stubbles,
plant matter
Page 42 Insect and allied pests of oats
Pest Appearance Damage Where found Thresholds Control options
Seedling pests
Aphids
Aphids: Corn aphid
(Rhophalosiphum maidis),
oat/ wheat aphid (R. padi)
Corn aphids are dark blue-green to grey green .
Oat aphids vary in colour from olive green to blackish
green but all have reddish patch on the tip of their
backs.
Are vectors of barley yellow dwarf
virus, refer to Diseases section.
Plants are most vulnerable to the
effects of the virus within the first
8-10 weeks after emergence.
Corn aphids are usually found in the
furled leaves of tillers.
Oat aphids are usually found on the
outside of tillers.
BYDV can be spread by low aphid
numbers, especially by winged aphids
flying into crops. Low numbers are difficult
to detect.
Assess your BYDV risk by looking at the
Departments crop disease web site.
Chemical applications are recommended only if there is
a high risk of aphid migrations. Recommended to apply
sprays at 3 and 7 weeks post emergence.
Beetle
Cockchafers:
Heteronyx
(Heteronyx obsesus)
Cockchafer larvae are ‘c’ shaped creamy, white grubs
that range in size from 5 -20 mm.
Cockchafer larvae feed underground
on plant roots.
Many native cockchafers are present
in soil, under the roots of crops.
Only Heteronyx is known to cause
extensive crop damage.
3-5 Heteronyx grubs per shovel full of
soil can cause crop damage especially
if seedlings do not have extensive root
systems.
Trials have shown that applications of chlorpyrifos as
a seed dressing at sowing are able to control this pest.
Higher seeding rates are another option if large numbers
of cockchfers are found before sowing.
Caterpillars
Webworm
(Hednota spp)
I Pale to deep brown body colour with dark head. Up to
15 mm in size, found in web lined .tunnels
Sever leaves or whole plants which
they scatter on the ground or pull
into holes at the base of plants..
Feed at night, found in web lined
tunnels in the ground usually with
plant part protruding.
25 % of seedlings are damaged, at or just
after emergence.
Grassy situations favour survival. If seeding post
pasture, good control of weeds prior to seeding is
recommended.
Cutworms
(Agrotis spp.)
Stout-bodied caterpillars up 50 mm in size found in soil
at the base of plants.
Chewed through stems at ground
level.
Feed at night and hide in soil during
the day.
2 to 3 cutworm caterpillars per square
metre.
Paddocks with good weed control for several weeks
before sowing are less at risk.
Earwig
European earwig 12-20 mm in length, dark shiny brown with pale yellow
legs and pincers.
Cause shredding damage to tillers,
rarely cause plant death but can
slow down plant development,
Under debris, clods of soil. Reducing stubble residues in paddocks known to
harbour earwigs will help to keep their numbers lower.
Lucerne
flea
Lucerne flea
(Sminthuris viridis)
Plump, roundish body, up to 3 mm in size. Greenish in
colour with brown and yellow mottled pattern. Jumps
upward when disturbed.
White windows on leaves. On weeds and seedlings. Consider control measures if holes are
increasingly being found on leaves.
Commonly found on soils with loam or clay texture
Mites
Balaustium mite
(Balaustium medicagoense)
Round body (up to 2 mm) with stout hairs, brown-red
in colour.
Bleached white lesions on seedling
leaves.
On weeds, soil and seedlings. Look for white bleaching on extensive
areas of leaves and stress caused to
plants.
Economic damage only occurs if these mites are present
in very high numbers, especially if seeding into green
bridge or if crop is moisture stressed. Under good
growing conditions crops outgrow damage.
Earthmites:
Redlegged earth mite
(Halotydeus destructor)
Blue oat mite
(Penthalus spp.)
Very small mites up to 1 mm with a black body and
red legs.
Blue oat mites have red spot on black body.
Leaves appear bleached.. On weeds, soil and seedlings. Look for bleaching on extensive areas of
leaves and stress caused to plants.
Economic damage only occurs if these mites are present
in very high numbers, especially if seeding into weedy
paddocks or if crop is moisture stressed. Under good
growing conditions crops often outgrow moderate
damage.
Slugs
Black keeled slug
(Milax gagates)
Reticulated slug
(Deroceras reticulatum)
Black keeled slugs are black in colour; Reticulated
slugs are light grey in colour.
Chewed leaves or whole plants.
They sometimes feed on lupin
seeds at seeding. Slime trails may
sometimes be seen.
On plants at night or hidden under
clods, trash, or other objects during
the day.
Black keeled slugs: 1-2 per m2.
Reticulated slugs: 5 per m2.
Baits are best applied prior to seeding. Multiple
applications are recommended.
Snails
White Italian snail
(Theba pisana)
White Italian snails have white shells, mostly with
broken brown bands in the line of the spiral. Some are
all white. Shells are up to 24 mm in width.
Chewed leaves. Slime trails may
sometimes be seen.
On leaves, stems or on other nearby
objects.
20 or more snails per m2.Other control measures such as weed control is required
in addition to baiting to achieve long term control. Baits
are best applied prior to seeding. Multiple applications
are recommended.
Vineyard snail
(Cernuella virgata)
Vineyard snails have shells up to 20 mm wide with a
continuous brown band.
Small pointed snail
(Cochlicella barbara)
Small pointed snail has a light brown conical shell up to
10 mm long.
40 or more snails per m2.
Weevil
Desiantha weevil
(Steriphus diversipes)
Larval stage attacks cereals, larvae are white, legless,
6 mm long with orange brown heads.
Feed on underground part of plants,
leading to slow plant growth or
plants may wilt and die and are
easily pulled from the ground.
Under the soil, Sometimes are difficult
to find.
If adult desiantha weevils were present in
the previous years crop or present in the
paddock prior to seeding it is likely there
will be larvae present in the soil.
Seed treatments are the only recommendation for the
control of this pest.
Head emergence - to grain ripening
Aphids
Aphids: Corn aphid
(Rhophalosiphum maidis),
oat/ wheat aphid (R. padi)
Corn aphids are dark blue-green to grey green .
Oat aphids vary in colour from olive green to blackish
green but all have reddish patch on the tip of their
backs.
Heavy infestations can blacken
heads and flag leaves, cause yield
losses by reducing grain weight.
Colonies develop on the outside of
tillers from the base upwards, on
stems, nodes and backs of mature
leaves, starting any time between late
tillering and grain filling.
If 50% or more of plants are infested
with 15 or more aphids consider control
measures.
Inspect numerous spots throughout paddock and check
tillers at random. Aphid infestations can be controlled by
parasitic wasps and other beneficials, consider applying
soft chemical options to keep predators intact.
Caterpillars
Armyworm:
Most common are-
Inland army worm
(Persectania dyscrita);
Southern armyworm
(Leucania convecta)
Insert picture of
armyworm here
Brown caterpillars with 3 longitudinal white stripes on
collar behind head, grow up to 40 mm in size.
Have green to straw coloured droppings size of match
head, usually found in crop rows.
Chew panicle causing grain to fall. On plant or under leaf litter, but prefer
rye grass.
Check crop regularly after flag leaf
emergence, if maturing crops have 10 or
more caterpillars per square metre control
will be justified.
If large caterpillars are found when grain is ripening,
apply chemical control. Effectiveness of spray
applications is dependent on
good penetration into the crop, which can be difficult to
achieve in thick canopy crops.
TABLE 10. Identification of oat pests and cultural control options
Page 43 Insect and allied pests of oats
Pest Appearance Damage Where found Thresholds Control options
Seedling pests
Aphids
Aphids: Corn aphid
(Rhophalosiphum maidis),
oat/ wheat aphid (R. padi)
Corn aphids are dark blue-green to grey green .
Oat aphids vary in colour from olive green to blackish
green but all have reddish patch on the tip of their
backs.
Are vectors of barley yellow dwarf
virus, refer to Diseases section.
Plants are most vulnerable to the
effects of the virus within the first
8-10 weeks after emergence.
Corn aphids are usually found in the
furled leaves of tillers.
Oat aphids are usually found on the
outside of tillers.
BYDV can be spread by low aphid
numbers, especially by winged aphids
flying into crops. Low numbers are difficult
to detect.
Assess your BYDV risk by looking at the
Departments crop disease web site.
Chemical applications are recommended only if there is
a high risk of aphid migrations. Recommended to apply
sprays at 3 and 7 weeks post emergence.
Beetle
Cockchafers:
Heteronyx
(Heteronyx obsesus)
Cockchafer larvae are ‘c’ shaped creamy, white grubs
that range in size from 5 -20 mm.
Cockchafer larvae feed underground
on plant roots.
Many native cockchafers are present
in soil, under the roots of crops.
Only Heteronyx is known to cause
extensive crop damage.
3-5 Heteronyx grubs per shovel full of
soil can cause crop damage especially
if seedlings do not have extensive root
systems.
Trials have shown that applications of chlorpyrifos as
a seed dressing at sowing are able to control this pest.
Higher seeding rates are another option if large numbers
of cockchfers are found before sowing.
Caterpillars
Webworm
(Hednota spp)
I Pale to deep brown body colour with dark head. Up to
15 mm in size, found in web lined .tunnels
Sever leaves or whole plants which
they scatter on the ground or pull
into holes at the base of plants..
Feed at night, found in web lined
tunnels in the ground usually with
plant part protruding.
25 % of seedlings are damaged, at or just
after emergence.
Grassy situations favour survival. If seeding post
pasture, good control of weeds prior to seeding is
recommended.
Cutworms
(Agrotis spp.)
Stout-bodied caterpillars up 50 mm in size found in soil
at the base of plants.
Chewed through stems at ground
level.
Feed at night and hide in soil during
the day.
2 to 3 cutworm caterpillars per square
metre.
Paddocks with good weed control for several weeks
before sowing are less at risk.
Earwig
European earwig 12-20 mm in length, dark shiny brown with pale yellow
legs and pincers.
Cause shredding damage to tillers,
rarely cause plant death but can
slow down plant development,
Under debris, clods of soil. Reducing stubble residues in paddocks known to
harbour earwigs will help to keep their numbers lower.
Lucerne
flea
Lucerne flea
(Sminthuris viridis)
Plump, roundish body, up to 3 mm in size. Greenish in
colour with brown and yellow mottled pattern. Jumps
upward when disturbed.
White windows on leaves. On weeds and seedlings. Consider control measures if holes are
increasingly being found on leaves.
Commonly found on soils with loam or clay texture
Mites
Balaustium mite
(Balaustium medicagoense)
Round body (up to 2 mm) with stout hairs, brown-red
in colour.
Bleached white lesions on seedling
leaves.
On weeds, soil and seedlings. Look for white bleaching on extensive
areas of leaves and stress caused to
plants.
Economic damage only occurs if these mites are present
in very high numbers, especially if seeding into green
bridge or if crop is moisture stressed. Under good
growing conditions crops outgrow damage.
Earthmites:
Redlegged earth mite
(Halotydeus destructor)
Blue oat mite
(Penthalus spp.)
Very small mites up to 1 mm with a black body and
red legs.
Blue oat mites have red spot on black body.
Leaves appear bleached.. On weeds, soil and seedlings. Look for bleaching on extensive areas of
leaves and stress caused to plants.
Economic damage only occurs if these mites are present
in very high numbers, especially if seeding into weedy
paddocks or if crop is moisture stressed. Under good
growing conditions crops often outgrow moderate
damage.
Slugs
Black keeled slug
(Milax gagates)
Reticulated slug
(Deroceras reticulatum)
Black keeled slugs are black in colour; Reticulated
slugs are light grey in colour.
Chewed leaves or whole plants.
They sometimes feed on lupin
seeds at seeding. Slime trails may
sometimes be seen.
On plants at night or hidden under
clods, trash, or other objects during
the day.
Black keeled slugs: 1-2 per m2.
Reticulated slugs: 5 per m2.
Baits are best applied prior to seeding. Multiple
applications are recommended.
Snails
White Italian snail
(Theba pisana)
White Italian snails have white shells, mostly with
broken brown bands in the line of the spiral. Some are
all white. Shells are up to 24 mm in width.
Chewed leaves. Slime trails may
sometimes be seen.
On leaves, stems or on other nearby
objects.
20 or more snails per m2.Other control measures such as weed control is required
in addition to baiting to achieve long term control. Baits
are best applied prior to seeding. Multiple applications
are recommended.
Vineyard snail
(Cernuella virgata)
Vineyard snails have shells up to 20 mm wide with a
continuous brown band.
Small pointed snail
(Cochlicella barbara)
Small pointed snail has a light brown conical shell up to
10 mm long.
40 or more snails per m2.
Weevil
Desiantha weevil
(Steriphus diversipes)
Larval stage attacks cereals, larvae are white, legless,
6 mm long with orange brown heads.
Feed on underground part of plants,
leading to slow plant growth or
plants may wilt and die and are
easily pulled from the ground.
Under the soil, Sometimes are difficult
to find.
If adult desiantha weevils were present in
the previous years crop or present in the
paddock prior to seeding it is likely there
will be larvae present in the soil.
Seed treatments are the only recommendation for the
control of this pest.
Head emergence - to grain ripening
Aphids
Aphids: Corn aphid
(Rhophalosiphum maidis),
oat/ wheat aphid (R. padi)
Corn aphids are dark blue-green to grey green .
Oat aphids vary in colour from olive green to blackish
green but all have reddish patch on the tip of their
backs.
Heavy infestations can blacken
heads and flag leaves, cause yield
losses by reducing grain weight.
Colonies develop on the outside of
tillers from the base upwards, on
stems, nodes and backs of mature
leaves, starting any time between late
tillering and grain filling.
If 50% or more of plants are infested
with 15 or more aphids consider control
measures.
Inspect numerous spots throughout paddock and check
tillers at random. Aphid infestations can be controlled by
parasitic wasps and other beneficials, consider applying
soft chemical options to keep predators intact.
Caterpillars
Armyworm:
Most common are-
Inland army worm
(Persectania dyscrita);
Southern armyworm
(Leucania convecta)
Insert picture of
armyworm here
Brown caterpillars with 3 longitudinal white stripes on
collar behind head, grow up to 40 mm in size.
Have green to straw coloured droppings size of match
head, usually found in crop rows.
Chew panicle causing grain to fall. On plant or under leaf litter, but prefer
rye grass.
Check crop regularly after flag leaf
emergence, if maturing crops have 10 or
more caterpillars per square metre control
will be justified.
If large caterpillars are found when grain is ripening,
apply chemical control. Effectiveness of spray
applications is dependent on
good penetration into the crop, which can be difficult to
achieve in thick canopy crops.
TABLE 10. Identification of oat pests and cultural control options
Insect and allied pests of oats
Page 44
alpha- cypermethrin
100 g/L
alpha- cypermethrin
250 g/L
beta-cyfluthrin
25 g/L
bifenthrin
100 g/L
chlorpyrifos
300 g/L
chlorpyrifos
500 g/L
cypermethrin
200 g/L
cypermethrin
250 g/L
deltamethrin
27.5 g/L
dimethoate
400 g/L
endosulfan
350 g/L
Pre-emergent ONLY
esfenvalerate
50 g/L
gama
cyhalothrin
150 g/L
imidachloprid
lambda-cyhalothin
250 g/L
methidathion
400 g/L
methomyl 225 g/L
omethoate
290 g/L
permethrin
40:60
500 g/L
Pirimicarb 500g/kg
phosmet
150g/L
Seedling pests
Aphids
(for BYDV control) 125 250 or
500
100 -
300 10 - 15 seed
dressing
12 or
18
Cutworm 75 700 -
900 75 200 70 10-15 12 or
18 25
Desiantha larvae seed
dressing
Lucerne flea 70 40 - 85 90 -
200 100
Earthmites 50 -100 200 50 -
100 140 50-75 55 - 85 500 -
1000 8 9 90 -
200 100 250 -
350
Webworm 75 100 -
200 100 300 75 200 70 10 12 50
Head emergence - to grain ripening
Aphids (feeding
damage)
500 or
1,000 500
150-
300 g/
ha
Armyworm 160-
240 96 400 NIL 1200-
1500 700-900 170 135 200-
500 1400 1000-
1500
Table 11. Registered insecticides for control of pests of Oats (Rates are given as mL/ha unless
specified otherwise
Insect and allied pests of oats
Page 45
The only option if these invertebrates are
found in numbers that exceed allowable
thresholds at grain recievals is to clean the
grain.
Methods to decrease the number of
vagrant insects in grain or hay:
Swath cereals at a height of 150 mm.
This allows the swath to form above the
ground, supported by the stubble. If the
swath is close to or on the ground, it is
more likely that vagrant insects will be
harvested with the grain or baled.
Harvest swaths or bale oats for hay as
soon as swaths are dry enough. The
longer that swaths are left unharvested,
the more vagrant invertebrates use them
as a refuge, consequently increasing the
number of insects that are harvested with
the grain or baled for hay.
Harvest swaths or bale for hay during the
hottest part of the day. Most insects (apart from snails) are found under the swath
during the hottest part of the day. However at night or under cool conditions, insects
move out from under the swath and up onto the top of the swath, where they are
more likely to be harvested with the grain or baled.
• Pests such as snails are present throughout swaths. If snails are present, control
measures need to be put in place at seeding to decrease snail numbers at harvest/
baling.
Using insecticidal sprays under swaths is not effective
Some growers have used insecticidal sprays under swaths to deter insects from using
swaths as a refuge. As the insects are not feeding on plant material under the swath, most
insecticides are not effective. Trials have shown that spraying under swaths does not
reduce the number of insects using the swath as a refuge. Additionally, no insecticides
are registered for this use as it may lead to chemical contamination of the grain
and rejection by national and international grain markets.
Direct harvested grain contains fewer vagrant insects
Trials have shown that directed harvested grain contains fewer vagrant insects but if
grain is harvested at night, more vagrant insects can be found in the harvested grain.
If snails are present within paddocks, they can be found sheltering in the head of the
crop at harvest, consequently becoming a grain contaminant. Controlling snails early in
the season at crop germination will decrease numbers and decrease the need to clean
grain for them.
Grain contaminated with insects
Insect and allied pests of oats
Page 46
Stored grain pests
Inspect stored grain for insects at least once a month in order to prevent severe
infestations. Test for the presence of insects by checking samples of the stored grain
with a grain sieve from top and bottom of the silo or pitfall traps in the headspace of the
silo. Condensation in the headspace in autumn is a sure sign insects are creating the
moisture somewhere in the silo. Grain insects reduce the quality of oats by reducing
the germination of the grain, eating and contaminating feed intended for livestock and
re-infesting machinery.
Important pests of stored oat grain are listed in Table 12.
Good hygiene of grain storage areas is strongly recommended. Other grain storage
control includes:
• coolinggrainwithaeration
• fumigatingsealedsiloswithphosphinegeneratingtablets
• applyingmalathioninsecticidebutbeawareMalathionresistanceiswidespreadand
it may not be effective
• treatinggrainbymixingwithDryacide.
When treating stored grain, growers need to be aware of the Maximum Residue
Limits (MRL) for 60 chemicals that were introduced by Japanese buyers in 2006 and
are likely to be introduced by some other buyers. To conform with the MRL, a grower
must observe the withholding period listed on product packaging.
For further information on the control of stored oat grain pests can be found on the
DAFWA website www.agric.wa.gov.au and the GRDC stored grain website www.
storedgrain.com.au . Two publications that are essential reading are ‘Hygiene and
structuraltreatmentsforgrainstorages-GRDCFactSheetSept2010and‘Fumigating
with phosphine other fumigants and controlled atmospheres’ GRDC booklet 2011.
Acknowledgements
Much of the information in this section has come about from the research conducted by
various Department of Agriculture and Food Entomologists that have worked on pests
of Cereals over many years.
Table 12. Important primary and secondary pests of stored oat grain
Primary Secondary
Lesser grain borer (Rhyzopertha dominica) Rust-red flour beetle (Tribolium castaneum)
Granary weevil (Sitophilus granarius) Confused flour beetle (Tribolium confusum)
Rice weevil (Sitophilus oryzae) Saw-toothed grain beetle (Oryzaephilus surinamensis)
Angoumois grain moth (Sitotroga cerealella) Flat grain beetle (Cryptolestes spp.)
Warehouse moth (Ephestia spp.)
Warehouse beetle (Trogoderma variable)
Making quality hay
Harvest
Page 47
Harvest
Blakely Paynter, Kellie Winfield
When to direct harvest grain
If the crop ripens and dries evenly (to less than 12 per cent moisture), direct harvesting
of the crop is the most economical way to harvest oats for grain. Harvest oats as soon
as the crop is ripe to reduce grain shedding.
Non-dwarf and other varieties that are likely to shed or lodge should be harvested
earlier than varieties less likely to shed or lodge.
To reduce harvesting delays, the grain can be direct harvested with the moisture
content above 12 per cent and then placed under aeration or through a grain dryer to
reduce the moisture content.
When to swath grain
If the oat crop is uneven in maturity or the climate does not allow for rapid drying of
grain, growers can swath the crop. Swathing evenly ripens the crop and allows
timelier harvesting. Swathing also helps minimise crop losses due to shedding
and lodging.
Swathing can begin when the grain moisture content is below 35 per
cent and the grain is at the medium dough stage, so it is hard but
can still be dented with the thumbnail. Avoid swathing too early,
when the grain is not fully developed, as this will result in small
pinched grain. Also, do not swath when the ground is wet after
rain.
Swathed grain should be harvested as soon as possible,
ideally within 10 days of swathing. If swaths are left too long
and are subjected to long periods of wetting (more than 25
mm of rain over four to eight days), grain may sprout and
become stained and may become contaminated with field
insects.
As a general rule crops that are likely to yield less than 2 t/ha
should not be swathed.
Storage of grain oats
Correct storage of grain oats is particularly important when
destined for human consumption. Before harvest, growers need
to clean silos and surrounding areas and grain handling equipment.
Grain stores need to be maintained and kept water tight. Water
will cause moulding and sprouting of grain which is unacceptable if
delivered.
The maximum moisture content at which oats can be safely stored is 12.5 per
cent unless the temperature is reduced to below 15°C. Above the safe limit, fungi
may develop and cause grain spoilage.
Stored grain needs to be protected from insect infestation. Infestations usually occur
within three months, even in situations where risk is minimised by good hygiene.
Storing oats at a temperature below 20°C and a moisture content of less than 12.5 per
cent should provide a shelf life of at least 12 months. Aeration is necessary for long-
term storage of oats to maintain cool temperatures and reduce loss in grain quality
from moisture, grain insects and mould.
Making quality hay
Page 48
Making quality hay
Making quality hay
Raj Malik, Blakely Paynter, Kellie Winfield
The oaten hay market in Western Australia has developed significantly over the past 15
years. Export hay is sold to Japan, Korea, Taiwan and the Middle East. Hay is also used
domestically by dairies, feedlots and the horse industry. Japan is our largest export
customer, purchasing around 85% of Western Australian export hay produced from
2001 – 2006. Over 650,000 tonnes of export hay was produced by Western Australia in
2005/06.
The Japanese market is increasingly demanding high quality hay, particularly as Australian
hay exporter’s work with Japanese buyers to show them why they should purchase our
forage versus forage produced in another country. As a result of an increased focus on
the quality of hay for the export market, interest in quality from the domestic market has
also grown. The quality demand from the domestic market however does vary more from
year to year depending on the availability of home produced forage and other feeds.
Choice of variety
For export hay, many export hay companies have preferred varieties they will receive
whilst others have no preference. Check with your hay processor prior to planting for
their list of preferred varieties. Often they will recommend growing an oat variety suited
to your region.
Many common grain varieties (such as Carrolup, Wandering A and Winjardie) are grown
successfully for export and domestic hay. The National Oat Breeding Program has also
recently released a range of specialist hay varieties including Brusher A, Kangaroo A,
Mulgara A, Wintaroo A and Tungoo A. These specialist varieties are best suited to
growers who grow large areas of oats for hay or with specialised hay production systems.
Older hay varieties such as Massif, Swan and Vasse are not widely accepted by export
hay processors as their stems tend to be too thick.
Whilst variety will influence hay quality, cutting the hay at the correct time and growing
it with appropriate management and inputs is the key to the successful production of
high quality hay for both domestic and export use.
Quality parameters for hay
Good colour and aroma, sweet taste and fine texture are of major importance to
export hay buyers. Hay processing companies in Western Australia also grade based
on nutritional value. The number of grades and even grading systems differ between
hay processors. Some companies have five grades, others have four and some grade
based on a 100 points system. The emphasis on particular parameters is also different
between processors and is subject to change depending on the season. Contact your
hay processor when planning your program to determine whether their requirements
suit you.
Table 13 provides a general guideline of the target quality required in oaten hay for
receival into different grades. Unlike grain there is no common standard on which hay
is received. Hay should have a maximum bale of moisture of 14 per cent at delivery to
ensure that it does degrade or spoil during storage. Some export standards are as low
as 12 per cent moisture. High moisture can also cause self combustion during storage.
Interest in oat hay for the dairy, feedlot and horse industries has increased in recent
years due to the improvements in hay quality standards brought about by demand from
the export market. In most cases Grade 2 hay will be sold by exporters to the domestic
market, however annual quality requirements will depend on the price of alternative
product used in livestock rations. In many cases the domestic market is loyal to suppliers
who continually supply the right product throughout the year and can deliver on time.
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Table 13. Typical target quality standards to meet different export hay requirements in Western Australia
Parameter Premium 1 Premium 2 Grade 1 Grade 2 Description
Crude protein 4–10 <4 <4 <4 CP is a measure of the total protein of the hay.
(CP) (%) It measures both true protein and non-protein sources
of nitrogen. CP is used in developing rations.
Water soluble 18–25 14–23 10–18 6–18 WSC is a measure of plant sugars (sweetness) and is used
carbohydrates as a guide to the palatability of the hay. Plant sugars are an
(WSC) (%) important source of energy to the animal.
Over 20% WSC is preferred.
Estimated <9.5 <9.5 <9.5 <9.5 EstME measures the amount of energy available per kg of
metabolisable hay dry matter. The available energy in the hay rises as
energy (estME) digestibility and dry matter increase.
(MJ/kg DM)
Acid detergent 30–35 32–35 36–38 37–40 ADF is an estimate of the proportion of the hay not
fibre (ADF) (%) digestible to animals. As ADF increases, the hay is less
digestible and food conversion efficiency decreases.
Neutral 55 55–59 57–60 60–64 NDF is a measure of how much of the hay is plant cell wall.
detergent fibre Plant cell wall provides ‘bulk’ rather than nutrients to the
(NDF) (%) diet. Whilst some ‘bulk’ is required for rumen functionality
in ruminants, high NDF can limit feed intake.
In vitro 58–60 57–58 56–58 53–57 IVD and DMD are measures of the proportion of the diet
digestibility (IVD) that an animal is able to digest and absorb. If hay is 66%
or digestible digestible, an animal fed 1000 g of hay would digest 660 g
dry matter and produce 340 g of manure. Animals fed hay with a low
(DMD) (%) IVD or DMD can lose condition regardless of how much
feed they intake.)
Stem thickness 6–12 8–12 9–12 10–12 Hay with fine, stems is generally preferred, as it
(mm) contains less fibre in the cell walls.
Hay grown for export is required to meet a number of other crop hygiene requirements
including:
Annual ryegrass toxicity
All export hay must be subjected to a compulsory sampling and testing protocol designed
to ensure that there is a minimum risk of it being contaminated by the bacterium that
causes annual ryegrass toxicity. Livestock deaths caused by annual ryegrass toxicity
poisoning from Australian hay or straw exports in an importing country could devastate
the Australian hay and straw export industry. If contamination by this bacterium is a
potential problem, look to implement an annual ryegrass toxicity management program
through the introduction of twist fungus or Safeguard A ryegrass.
Weeds
Export hay requires a nil presence of toxic plants and double gees. Most processors have
a limit of 1% of broad leaf plants and 5% of other cereals/rye grass/wild oats.
Foreign/animal material
There is a zero tolerance of foreign material including dirt, stones, sticks, insects, wool,
wire and carcases in export hay. Paddock management requires contaminants to be
removed prior to planting.
Disease
A maximum of 10% affected leaves is allowed by most processors. Also check withholding
periods on labels of all fungicides being considered for use. Do not apply fungicide if the
likely cutting date is within a withholding period. For best control, plant disease resistant
varieties.
Chemical residue
Export markets (particularly Japan) expect a clean and green product from Australia and
thus limited use of chemicals. In 2006 Japan introduced regulations to enforce the safety
of imported animal feeds which included the establishment of MRL’s for 60 chemicals in
Making quality hay
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feeds including hay and grains such as wheat, barley and oats. Speak to your exporter
about their requirements for documenting chemical use.
Nitrates
The desired nitrate level in hay is < 500 mg/kg. Under infrequently experienced conditions
oat plants, like other cereals, can accumulate much greater quantities of nitrates than
this, and these are conserved in the process of hay making. In these situations the
hay may be toxic, and in some cases the toxic potential can be enhanced if the hay is
dampened by rain.
Export hay has a strong emphasis on water soluble carbohydrates, particularly for the
Japanese market. This is mainly driven by the Japanese buyers who physically taste the
hay and use this concept to sell the hay to dairy farmers. The reasoning is that hay, which
is high in water soluble carbohydrates is usually high in digestible dry matter and low in
fibre and therefore more palatable, resulting in higher intake and higher production. Hay
exported to Japan must also be of excellent green colour, texture, smell and taste. These
characteristics are also generally sought by the domestic market, however, there appears
to be little evidence that animals prefer hay due to its colour but aroma has been found
to have an influence for some animals.
Domestic hay quality has an emphasis on nutritional value, particularly crude protein
and metabolisable energy. The desired level for crude protein is > 8% and metabolisable
energy is > 9.0 MJ/kg dry matter. Many of the hygiene requirements for export hay are
also relevant to the production and marketing of hay for domestic use.
Hay cutting time
There is always a conflict of interest between growers and exporters. Growers are always
looking for higher yields while the exporters seek higher quality.
The optimum cutting time recommended by most processors is at the watery-ripe stage
(Z71) or earlier. When the top florets are squeezed at this stage, a clear watery liquid
appears (Figure 27). If the liquid is white, then the optimum stage of cutting has already
occurred. Test the crop at several places in the paddock. If more than half the paddock
is at the watery ripe stage, this is the perfect time to cut.
Cutting hay a week later than the watery ripe stage reduces the quality but it is still within
the acceptable range of export standards. This means that there is a five- to seven-
day window of opportunity before quality starts to fall below premium levels and starts
affecting returns. This gives growers some flexibility to accommodate contracting and
rainfall issues.
Rainfall events of 10 mm or over can
drastically reduce the quality of cut hay.
Therefore, it is important to consider
delaying cutting if a significant rainfall
event is forecast. Hay quality is most
at risk when exposed to rainfall events
between cutting and baling, resulting in
fading of colour, moulding and decline in
nutritive value.
Risk can be minimised if more than one
variety is planted. The cutting date will
vary with each variety, due to the different
maturing times. Just remember: ’You can’t
manage what you don’t observe and don’t
measure’.
Hay cut before the watery ripe stage has
the highest quality, but the penalty to the
Figure 26. Paddock inspection of crop growth
stage for hay cutting (Photo: Raj Malik DAFWA).
Making quality hay
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Table 14. Change in hay quality when cut was delayed by two weeks from watery ripe stage
(data is an average of six varieties)
Season (May–October rainfall)
2005 (362 mm) 2006 (186 mm)
Z71 Z71 + Z71 Z71 + LSD (p=0.05)
14 days 14 days
Stem thickness (mm) 5.7 5.6 5.7 5.8 NS
Leaf greenness (SPAD) 50.2 40.0 48.6 17.7 3.0
Crude protein (%) 4.1 2.4 6.6 5.6 0.9
ADF (%) 28.2 27.3 28.3 31.5 1.1
NDF (%) 47.7 45.2 47.5 53.2 1.2
IVD (%) 58.9 57.6 63.2 59.3 1.0
estME (MJ/kg DM) 8.4 8.1 9.0 8.4 0.2
WSC (%) 35.5 35.1 24.9 16.5 1.8
grower is lower hay yields. Early cut hay usually has thinner stems, more crude protein,
slightly lower fibre (ADF and NDF) levels, is more digestible and has higher metabolisable
energy than hay cut after watery ripe.
Whilst cutting hay after the watery ripe stage may result in increased hay yield, the hay is
of lower quality. Late cutting (14 days or more after the water ripe stage) usually results in
hay with a poorer colour, less crude protein, lower digestibility, and lower metabolisable
energy (Table 14). The impact of late cutting on stem fibre (ADF and NDF) levels and
water soluble carbohydrates is greatest in seasons where there is a dry finish (for example
compare the data from the dry season of 2006 with that of the wetter season on 2005
in Table 14).
Impact of variety on cutting date
Table 15 groups different oat varieties into a range of maturity classes, based on their
duration to watery ripe when sown between late May to early June in the region between
Northam and Katanning. Groups are based on expected differences in maturity relative
to Carrolup and are calculated from flowering date trials which were monitored three
times per week.
Large differences in duration to watery ripe were noted among oat varieties. The difference
between the earliest (Yilgarn) and latest (Massif) was over 30 days. In the hay varieties,
Brusher A generally reached the watery ripe stage first, followed by Marloo, Swan,
Winjardie and Kangaroo A and finally by Wintaroo A. Brusher A was ready for cutting
Figure 27. The watery ripe stage (left) is reached just before milk development (right). When the
grain is squeezed a watery green/white liquid will come out, opposed to a milky white liquid (right).
(Photo: Kellie Winfield DAFWA)
Making quality hay
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at a similar time to Carrolup. Wandering A, another popular variety cut for hay, reached
the watery ripe stage slightly earlier than Carrolup.
Impact of sowing date on cutting date
The maturity group ranking is based on the flowering date of oats when sown in late
May and early June. Figure 28 shows the change in duration to watery ripe (optimum
cutting stage) as the date of seeding is delayed for eight varieties representing different
maturity groups.
As oat varieties modify their flowering date in response to changes in daylength (due
to location) and temperature (due to season and sowing date), some varieties are more
sensitive to particular sowing dates than others.
Needilup, Possum A, Swan and Winjardie are more sensitive to daylength than other
varieties. They are able to contract the period from sowing to watery ripe if seeding is
delayed into late June and July and lengthen the period from sowing to watery ripe if
seeding begins in late April.
This means that these varieties may flower at a different time relative to other varieties in
their same maturity group when sown in early May or late June. For example, Winjardie
Table 15. Maturity groups of 24 oat varieties grown in Western Australia based on the duration
to reach watery ripe when sown in late May to early June in the region between Northam and
Katanning
Maturity group
(days relative to Carrolup) Code Variety
Early spring -3 to -7 days E Coomallo, Hotham, Mitika A, Yilgarn, Pallinup, Possum A,
Wandering A
Medium spring -2 to +2 days M Brusher A, Carrolup, Euro, Kojonup A, Mortlock, Toodyay, Quoll A
Medium to late spring M–L Dalyup, Kangaroo A, Marloo, Potoroo, Swan,
+3 to +7 days Winjardie
Late spring +8 to +12 days L Wintaroo A Needilup A
Very late spring +18 to +22 days VL Vasse
Extremely late spring > +28 days EL Massif
18 Apr
28 Apr
8 May
18 May
28 May
7 Jun
4 Dec
24 Nov
14 Nov
4 Nov
25 Oct
15 Oct
5 Oct
25 Sep
15 Sep
17 Jun
27 Jun
7 Jul
17 Jul
27 Jul
6 Aug
Date sown
Date of watery ripe
Wandering Carrolup Kangaroo Wintaroo
Vasse Massif Dalyup Brusher
Figure 28. Dates on which varieties (representing different maturity groups) are projected to
reach watery ripe (optimum hay cutting stage) for a range of sowing dates from late April
through to early August (data from seasons of 2003, 2004 and 2005).
Making quality hay
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Cut hay crops at the watery ripe stage
(Z71) as this is the best compromise
between hay yield and hay quality.
SUMMARY
sown in late April may reach the watery
ripe stage some 14 days later than
Carrolup. When Winjardie is sown in late
May, it reaches the watery ripe stage 7
days later than Carrolup. A late June
sowing will reach watery ripe stage only
3 days later than Carrolup. Most varieties
follow the patterns exhibited by the variety
representing their maturity group in Table
15 and Figure 28.
It should be noted that a three-week delay
in sowing date results in a delay of about
7 to 10 days in cutting date for most
varieties sown in May and June (Figure 28).
For example, we would expect Carrolup
to be ready for hay cutting (watery ripe)
at Katanning about 11 October when
sown on 28 May and about 20 October
if seeding was delayed three weeks until
18 June.
When choosing varieties to sow it is
important to take into account their maturity group and likely differences in duration to
reach watery ripe. Depending on which varieties are chosen, sow each variety at the
appropriate time to spread the risk (so they are ready for cutting at staggered times).
Impact of season on cutting date
Average daily temperature influences the duration to watery ripe. In seasons or locations
with a higher than average temperature during winter, a shorter duration to watery ripe
(up to one week earlier than the predicted date) will result. Seasons with a lower than
average temperature may result in a later duration to watery ripe (up to one week later
then the predicted date).
Impact of location on cutting date
Flowering date trials conducted at Katanning and Northam show large differences in the
predicted date at which oat varieties will reach the watery ripe stage due to location.
This is due to differences in daylength and temperature between locations. During winter,
for example, Katanning has slightly shorter days and
slightly lower average temperatures. It takes an oat
crop sown at Katanning about 14 days longer to
reach the watery ripe stage than an oat crop sown
on the same day in May at Northam. When seeding is
delayed to June, the Katanning crop will reach watery
ripe about 10 days later than an oat crop sown at
Northam on the same day.
Hay cutting height
Cutting height, as a rule of thumb, is 15 cm (the height of a soft drink can). High yielding
crops and lodged crops may need to be cut slightly higher to ensure the weight of the
windrow is supported off the ground. Cutting higher may reduce the yield but has a
marked influenced on quality. Cutting too low will compromise the drying process and
the hay quality as the cut stems are too thick and discoloured, with a higher fibre content
and lower digestibility. There is also a greater risk of picking up more dirt while raking.
Figure 29. Freshly cut hay
(Photo: Raj Malik DAFWA)
Making quality hay
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Baling
The moisture content of baled hay is critical and baling high moisture hay should be
avoided at all costs. Hay baled at over 18 per cent moisture is at risk of developing mould
in the bale. There is also a risk of spontaneous combustion occurring when stored.
Export markets prefer baled hay with moisture content of less than 14 per cent; some
exporter standards are as low as 12 per cent moisture. At these low moistures the risk
of spontaneous combustion during storage is minimised. There is also a lower risk
of condensation dropping off the container roof onto the hay during transit, creating
wet patches and encouraging mould formation. High density bales do not dry readily
because of low air exchange rates and the insulating qualities of hay. Bales of 18 per
cent moisture may take many months to dry to an acceptable moisture content.
Judging exact moisture for baling is not easy, but two tests are as follows:
• Twist a few stems from the windrow and examine the joints for a show of moisture.
If moisture is evident, the crop is too moist.
• Use the bark test. Scratch the stem of the plant with a fingernail. The outer layer will
lift if it is too moist, but will not if the crop is dry enough.
Particular attention must be paid to
raking. A poor job will pick up dirt and
stones which will cause the hay to be
downgraded.
Storing hay
It is important to have hay in storage as
soon as possible after baling to prevent
any damage from weather exposure. Many
hay exporters will require growers to store
hay for long periods of time. Appropriate
storage will prevent weather damage (from
sun, rain and wind). Sheds should have at
least three walls (with the opening facing
away from prevailing weather). If floors
are not concrete, heavy duty black plastic
should be used to prevent moisture rising
into the bales. Moisture affected bales will
be rejected for export. Shed design should provide adequate air flow throughout the
stack to dissipate any heated hay which can lead to spontaneous combustion. A bonus
is often paid to growers who are able to store export hay on farm. Domestic hay will also
benefit from being stored under the same criteria as export hay.
The temperature of a stack can be checked with a temperature probe, crow bar or other
piece of solid steel. Leave the bar in the stack for approximately 2 hours. If the bar is
only just tolerable to touch after being removed from the hay stack, this indicates that
bale temperatures are greater than 60°C. If the temperature continues to rise, the stack
needs to be pulled apart. Tubular steel should not be used as this may allow air into the
stack and create an environment for combustion to occur.
Water and fire fighting equipment should be on hand to prevent shed fires. Bales that
have reached a high temperature may ignite as they are pulled apart and introduced to
a more available oxygen supply.
The exact cause of spontaneous fires in hay stacks is not fully understood. In most cases
it generally takes five to ten weeks for conditions to be right for combustion to occur,
although it can occur in as few seven days under ideal conditions. For a fire to occur
there is usually both respiration heating and biological heating (primary source) and then
exothermic heating (secondary source).
Figure 30. Baled hay in paddock
(Photo: Raj Malik DAFWA)
Further reading
Page 55
Making quality hay
Further reading
Co-operative Bulk Handling (2003) Swathing: A harvest management tool for Western
Australia.
Emery, R, Mangano,P & Michael, P 2005. Crop insects: the Ute Guide, Western Grain Belt Edition.
GRDC and Department of Agriculture and Food, Western Australia, South Perth.
Evans, L, Winfield, K & Paynter, B 2006. Fuel and fertiliser price rises and the bottom line
for hay production. Farmnote 179/2006. Department of Agriculture and Food, Western
Australia, South Perth.
Falconer, K-L & Bowden, B 2001. How much fertility are you removing when you export
hay and stubble from your farm? Farmnote 97/2001. Department of Agriculture and Food,
Western Australia, South Perth.
Kessell, D 2010. Annual ryegrass toxicity – current situation. Farmnote 417/2010.
Department of Agriculture and Food, Western Australia, South Perth.
MacLeod B, VA Vanstone, R Khangura and C Beard (2008). Root disease under intensive
cereal production systems. Department of Agriculture and Food Western Australia,
Bulletin 4732.
Malik, R 2009. Oaten hay production for small landholders. Farmnote 369/2009.
Department of Agriculture and Food, Western Australia, South Perth.
Mangano, P 2006. Armyworm in Cereal Crops. Farmnote 183. Department of Agriculture
and Food, Western Australia, South Perth.
Michael, P 1994. Cutworms pests of crops and pasture. Farmnote 59/1994. Department of
Agriculture and Food, Western Australia, South Perth.
Micic, S, Henry, K & Horne, P 2007. Identification and control of pest slugs and snails for
broadacre crops in Western Australia Bulletin 4713, Department of Agriculture and Food,
Western Australia, South Perth.
Newman, C 2002. Aeration – for preserving grain quality. Farmnote 24/2002. Department
of Agriculture and Food, Western Australia, South Perth.
Riethmuller, G 1996. Harvest loss estimation. Farmnote 104/1996. Department of
Agriculture and Food, Western Australia, South Perth.
Vanstone VA (2007). Root Lesion and Burrowing Nematodes in Western Australian
cropping systems. Department of Agriculture and Food Western Australia, Bulletin 4698.
http://www.agric.wa.gov.au/objtwr/imported_assets/content/pw/ph/par/bn2006_
nematodes_vvanstone.pdf
Vanstone V and Lewis J (2009). Plant parasitic nematodes fact sheet, Southern and
Western region, Managing cereal cyst and root lesion nematodes. GRDC.
Wallwork H (2000). Cereal Root and Crown Diseases. Grains Research and Development
Corporation and SARDI, Adelaide.
Winfield K, Paynter B & Malik R 2007. Oat hay quality for export and domestic markets.
Farmnote 209/2007. Department of Agriculture and Food, Western Australia, South
Perth.
Winfield K, Paynter B & Malik R, 2006. Determining the cutting date (watery ripe stage)
for oat hay. Farmnote 180/2006. Department of Agriculture and Food, Western Australia,
South Perth.
Winfield, K, Hall, M & Paynter, B 2007. Milling oat and feed oat quality: what are the
differences? Bulletin 4703, Department of Agriculture and Food, Western Australia, South
Perth.
Further reading
Page 56
Appendix 1.
Zwer, P & Faulkner, M 2006. Producing Quality Oat Hay, RIRDC publication 06/002.
Available at http://www.rirdc.gov.au/reports/FCR/06-002.pdf.
Zwer P et al. (2010). Oat variety sowing guide 2010. South Australian Research and
Development Institute.
Important websites
Australian Exporters Company (AEXCO): <www.aexco.com.au>
Australian Fodder Industry Association (AFIA): <www.afia.org.au>
Department of Agriculture, Wester n Australia, ‘Oat Productionin Western Australia’
<www.agric.wa.gov.au>
GRDC Stored Grain Website www.storedgrain.com.au
Appendix 1
Page 57
Appendix 1. Zadoks growth scale
(Compiled from The Wheat Book, Anderson & Garlinge 2000)
The Zadoks decimal growth scale is based on 10
cereal growth stages.
0 Germination
1 Seeding Growth
2 Tillering
3 Stem Elongation
4 Booting
5 Awn Emergence
6 Flowering (Anthesis)
7 Milk Development
8 Dough Development
9 Ripening
Each primary growth stage is divided into 10
secondary stages, extending the scale from 00 to
99. The early growth stages (1, 2 and 3) are referred
to most frequently. The Zadoks Growth Scale key
does not run chronologically from Z00 to 99. For
example, when the crop reaches three fully unfolded
leaves (Z13) it begins to tiller (Z20), before it has
completed four, five or six fully unfolded leaves
(Z14, 15, 16).
0: Germination
00: Dry seed
01: Start of water absorption
03: Seed fully swollen
05: First root emerged from seed
07: Coleoptile emerged from seed
09: First green leaf just at tip of coleoptile
1: Seedling growth
Count leaves on main stem only. Fully emerged
= ligule visible. Subdivide the score by rating the
emergence of the youngest leaf in tenths. For
example, 12.4 = two emerged leaves plus the
youngest leaf at 4/10 emerged.
10: First leaf through coleoptile
11: First leaf emerged
12: 2 leaves emerged
13: 3 leaves emerged
14: 4 leaves emerged
15: 5 leaves emerged
16: 6 leaves emerged
17: 7 leaves emerged
18: 8 leaves emerged
19: 9 or more leaves emerged
2: Tillering
Count visible tillers on main stem; that is, the
number of side shoots with a leaf blade merging
between a leaf sheath and the main stem.
20: Main stem only
21: Main stem and 1 tiller
22: Main stem and 2 tillers
23: Main stem and 3 tillers
24: Main stem and 4 tillers
25: Main stem and 5 tillers
26: Main stem and 6 tillers
27: Main stem and 7 tillers
28: Main stem and 8 tillers
29: Main stem and 9 or more tillers
3: Stem elongation
Generally count swollen nodes that can be felt on
the main stem. Report if dissection is used.
30: Pseudostem (youngest leaf sheath erection)
31: First node detectable
32: Second node detectable
33: Third node detectable
34: Fourth node detectable
35: Fifth node detectable
36: Sixth node detectable
37: Flag leaf just visible
39: Flag leaf ligule just visible
4: Booting
Score the appearance of the sheath of the flag leaf.
41: Flag leaf sheath extending
43: Boots just visible swollen
45: Boots swollen
47: Flag leaf sheath opening
49: First awns visible
5: Ear emergence from boot
51: Tip of ear just visible
53: Ear 1/4 emerged
55: Ear 1/2 emerged
57: Ear 3/4 emerged
59: Ear emergence complete
6: Anthesis (flowering)
Generally scored by noting the presence of emerged
anthers.
61: Beginning of anthesis (few anthers at middle
of ear)
65: Anthesis half-way (anthers occurring half
way to tip and base of ear)
69: Anthesis complete
7: Milk development
Score starch development in the watery kernel.
71: Kernel water ripe (no starch)
73: Early milk
75: Medium milk
77: Late milk
8: Dough development
Kernel no longer watery but still soft and dough-like
83: Early dough
85: Soft dough
87: Hard dough
9: Ripening
91: Grain hard, difficult to divide
92: Grain hard, not dented by thumbnail
93: Grain loosening in daytime
94: Over-ripe straw dead and collapsing
95: Seed dormant
96: Viable seed giving 50% germination
97: Seed not dormant
98: Secondary dormancy induced
99: Secondary dormancy lost
Crop establishment
Page 58
ResearchGate has not been able to resolve any citations for this publication.
Technical Report
Full-text available
The oaten hay market in Western Australia has developed significantly over the past 15 years. Japan has purchased on average 85% of Western Australian export hay produced from 2001-2006 with Korea, Taiwan, and the Pacific and Middle East regions taking up the remainder. Over 650,000 tonnes of export hay was produced by Western Australia in 2005/06. Market demand is increasing and production targets of 800,000 tonnes of export hay from Western Australia are likely over coming seasons. The Japanese market is increasingly demanding high quality hay, particularly as Australian hay exporters work with Japanese buyers to show them why they should purchase our forage versus forage produced in another country. As a result of an increased focus on the quality of hay for the export market, interest in quality from the domestic market has also grown. The quality demand from the domestic market however does vary more from year to year depending on the availability of home produced forage and other feeds. The guidelines in this Farmnote describe the acceptable quality of oaten hay for the export and domestic market.
Technical Report
Full-text available
Key Messages • Knowledge of the maturity group of your hay variety and how it responds to changes in sowing date can assist the planning of what variety to sow. Sowing them at appropriate times can spread the risk (so they are ready for cutting at staggered times). • The optimum stage for cutting hay is the watery ripe stage (Z71). At this stage, crushing a floret will squeeze out a watery solution (Figure 1). Some exporters may have different requirements for cutting time. Contact your exporter well before cutting time to determine their requirements. • In the event of rain occurring at the cutting stage, it is often better to delay cutting as the impact of rain on cut hay can often reduce hay quality more than a seven day delay in cutting date. • The duration from sowing to reaching the watery ripe stage is modified by location, season, sowing date and variety. • Twenty four oat varieties were grouped into six maturity groups (Table 1). Differences of over 30 days were noted in the duration to the watery ripe stage between the earliest variety (Yilgarn) and the latest variety (Massif). • Most varieties responded the same way to changes in sowing date (Figure 2). Four varieties-Needilup, Possum , Swan and Winjardie – differed in their response to sowing date relative to other varieties in the same maturity class. • A three week delay in sowing date results in only a 7 to 10 day difference in cutting date. • Crops sown at Katanning take between 10 to 14 days longer to reach the watery ripe stage as crops sown on the same day at Northam. • The information presented in this Farmnote are predicted dates based on actual trial data.
Technical Report
Full-text available
This Bulletin explains the differences between oat products used for human and animal consumption and the importance of the quality parameter to the quality of the end product. It also indicates why different varieties are suited to different end markets.
Technical Report
Full-text available
While increases in fuel prices between 2005 and 2006 had a significant impact on the gross margin for hay production, increased fertiliser prices had an even higher impact. Export hay production is still more profitable than grain production (although there is a higher risk involved). A 30c per litre rise in the cost of diesel fuel: - increases the cost of cutting, baling and stacking hay by $7.75/ha; 􀀍􀀀- increases the cost of carting medium sized hay bales 50 km by $1.05/t; and 􀀍􀀀- decreases the gross margin of oaten hay by $10.99/ha compared to grain by $4.70/ha. The 25% increase in fertiliser prices between 2005 and 2006 increased the nutrient replacement cost from growing oaten hay by $6.34/t of hay grown. As fertiliser and fuel prices continue to increase small producers will find it harder to be profitable. Smaller growers will need to assess their export hay production levels and level of investment against other production activities such as grain. Some level of investment in machinery or storage may be required to maintain profitability.
29 Foliar diseases35 Soil and plant testing services39 Insect and allied pests of oats48 Choice of variety
  • ............................................................................................... 24 Manganese.................................................................................................................................................................................................... 25 Weeds.................................................................................................................................................................................................................................. 26 Diseases........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... Hay.............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................. Micronutrients
Micronutrients – zinc, manganese and copper...............................................................................................24 Manganese....................................................................................................................................................................................................25 Weeds..................................................................................................................................................................................................................................26 Diseases..........................................................................................................................................................................................................................29 Foliar diseases..........................................................................................................................................................................................29 Virus Diseases...........................................................................................................................................................................................31 Chemical control of foliar diseases...............................................................................................................................34 Root and crown diseases...........................................................................................................................................................34 Nematodes....................................................................................................................................................................................................35 Soil and plant testing services..............................................................................................................................................39 Insect and allied pests of oats.........................................................................................................................................................40 Stored grain pests................................................................................................................................................................................46 Harvest..............................................................................................................................................................................................................................47 When to direct harvest grain...................................................................................................................................................47 When to swath grain..........................................................................................................................................................................47 Storage of grain oats........................................................................................................................................................................47 Making quality hay............................................................................................................................................................................................48 Choice of variety....................................................................................................................................................................................48 Quality parameters for hay........................................................................................................................................................48 Hay cutting time......................................................................................................................................................................................50 Baling....................................................................................................................................................................................................................54 Storing hay....................................................................................................................................................................................................54 Further reading......................................................................................................................................................................................................55 Page 6 @BULLET End use -Decide on whether you are growing for milling or feed. @BULLET Receival standards -Make yourself aware of the oat receival standards and quality segregations. Full details of oat receival standards can be obtained from CBH. (www.cbh.com.au). The oats are segregated into two grades -Oat 1 (formerly milling) and Oat 2 (formerly feed) -to reflect the quality and the markets into which these segregations are sold. Australia.
Crop insects: the Ute Guide, Western Grain Belt Edition
  • R Emery
  • Mangano
Emery, R, Mangano,P & Michael, P 2005. Crop insects: the Ute Guide, Western Grain Belt Edition. GRDC and Department of Agriculture and Food, Western Australia, South Perth.
How much fertility are you removing when you export hay and stubble from your farm? Farmnote 97
  • K-L & Falconer
  • Bowden
Falconer, K-L & Bowden, B 2001. How much fertility are you removing when you export hay and stubble from your farm? Farmnote 97/2001. Department of Agriculture and Food, Western Australia, South Perth.
Annual ryegrass toxicity-current situation
  • D Kessell
Kessell, D 2010. Annual ryegrass toxicity-current situation. Farmnote 417/2010. Department of Agriculture and Food, Western Australia, South Perth.
Root disease under intensive cereal production systems. Department of Agriculture and Food Western Australia
  • B Macleod
  • R Va Vanstone
  • C Khangura
  • Beard
MacLeod B, VA Vanstone, R Khangura and C Beard (2008). Root disease under intensive cereal production systems. Department of Agriculture and Food Western Australia, Bulletin 4732.
Oaten hay production for small landholders. Farmnote 369/2009. Department of Agriculture and Food
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Malik, R 2009. Oaten hay production for small landholders. Farmnote 369/2009. Department of Agriculture and Food, Western Australia, South Perth.