Tackling Contentious Invasive Plant Species: A Case Study of Buffel Grass in Australia

Abstract

Introduced plants that have both production values and negative impacts can be contentious. Generally they are either treated as weeds and their use prohibited; or unfettered exploitation is permitted and land managers must individually contend with any negative effects. Buffel grass (Cenchrus ciliaris) is contentious in Australia and there has been no attempt to broadly and systematically address the issues surrounding it. However, recent research indicates that there is some mutual acceptance by proponents and opponents of each others' perspectives and we contend that this provides the basis for a national approach. It would require thorough and on-going consultation with stakeholders and development of realistic goals that are applicable across a range of scales and responsive to regional differences in costs, benefits and socio-economic and biophysical circumstances. It would be necessary to clearly allocate responsibilities and ascertain the most appropriate balance between legislative and non-legislative mechanisms. A national approach could involve avoiding the introduction of additional genetic material, countering proliferation in regions where the species is sparse, preventing incursion into conservation reserves where it is absent, containing strategically located populations and managing communities to prevent or reduce dominance by buffel grass. This approach could be applied to other contentious plant species.

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PROFILE
Tackling Contentious Invasive Plant Species: A Case Study
of Buffel Grass in Australia
Anthony C. Grice
•
Margaret H. Friedel
•
Nadine A. Marshall
•
Rieks D. Van Klinken
Received: 8 February 2011 / Accepted: 18 October 2011 / Published online: 5 November 2011
Ó Springer Science+Business Media, LLC 2011
Abstract Introduced plants that have both production
values and negative impacts can be contentious. Generally
they are either treated as weeds and their use prohibited; or
unfettered exploitation is permitted and land managers must
individually contend with any negative effects. Buffel grass
(Cenchrus ciliaris) is contentious in Australia and there has
been no attempt to broadly and systematically address the
issues surrounding it. However, recent research indicates that
there is some mutual acceptance by proponents and oppo-
nents of each others’ perspectives and we contend that this
provides the basis for a national approach. It would require
thorough and on-going consultation with stakeholders and
development of realistic goals that are applicable across a
range of scales and responsive to regional differences in
costs, benefits and socio-economic and biophysical circum-
stances. It would be necessary to clearly allocate responsi-
bilities and ascertain the most appropriate balance between
legislative and non-legislative mechanisms. A national
approach could involve avoiding the introduction of addi-
tional genetic material, countering proliferation in regions
where the species is sparse, preventing incursion into con-
servation reserves where it is absent, containing strategically
located populations and managing communities to prevent or
reduce dominance by buffel grass. This approach could be
applied to other contentious plant species.
Keywords Contentious plants  Invasion  Policy 
Production  Strategy  Weed
Introduction
It is difficult and expensive to address the problems caused
by abundant, widespread invasive plants. Difficulties are
exacerbated for species that are also useful or desirable, or
perceived to be so by some interest groups, and contentions
often arise. Pasture introduction programs have contributed
significantly to the suite of contentious plants in Australia
(Cook and Dias 2006; Grice 2004; Grice and others 2008).
Some species introduced during these programs are highly
productive without being problematic; some are invasive
without being useful; others are simultaneously problem-
atic and productive (Lonsdale 1994). Progress with con-
tentious species requires practical and economic
biophysical solutions that are effective at large scales as
well as resolution of any contentions (Grice 2006). In this
paper we consider biophysical and social factors in
examining prospects and approaches for developing broad-
scale strategic solutions for one contentious naturalised
pasture species in Australia, buffel grass Cenchrus ciliaris
L. (syn. Pennisetum ciliare (L.) Link).
The Basis of Contention Over Buffel Grass
Buffel grass is arguably the most successful introduced
pasture grass in northern Australia (Humphreys 1967).
Early, incidental or accidental introductions probably took
place in the 1870s (Friedel and others 2006). Through the
twentieth century, buffel grass and other Cenchrus spp. were
included in pasture plant introduction programs, material
A. C. Grice (&)  N. A. Marshall
CSIRO, Ecosystem Sciences, Private Bag PO Aitkenvale,
Townsville, QLD 4814, Australia
e-mail: tony.grice@csiro.au
M. H. Friedel
CSIRO, Ecosystem Sciences, Alice Springs, NT, Australia
R. D. Van Klinken
CSIRO, Ecosystem Sciences, Brisbane, QLD, Australia
123
Environmental Management (2012) 49:285–294
DOI 10.1007/s00267-011-9781-6

being collected in various parts of the species’ native range
in Africa, the Middle East and southern Asia (Hall 2000).
There were many informal and formal releases of the species
in central, tropical and sub-tropical Australia and it was
widely promoted (Hall 2000). As a result it has naturalised
across much of mainland Australia (Australia’s Virtual
Herbarium 2010) and islands off the northern coast (Dixon
and others 2002) (Fig. 1), including in at least 53 of Aus-
tralia’s 85 Interim Biogeographical Regions (van Klinken
and others 2004). There is potential for further range
expansion (Lawson and others 2004).
Buffel grass is now common and widespread in Aus-
tralia, most notably in the centre and north. It is common in
many extensively used pastoral systems and substantial
increases in livestock carrying capacities have been
attributed to it (Chudleigh and Bramwell 1996; Hall 2000;
Friedel and others 2006). Buffel grass has also been used in
erosion control and restoration of areas degraded by live-
stock grazing (Keetch 1981). There are no reliable, detailed
national data on how much land has been sown to buffel
grass or over what area it has naturalised but it is clearly
economically important (Hall 2000; Friedel and others
2006).
At least since the early 1990s, concerns have been
expressed about possible negative environmental impacts
of buffel grass (Humphries and others 1991; Griffin 1993;
Friedel and others 2006). Several studies have attempted to
quantify them. In central Australia, buffel grass may reduce
or degrade refuges for threatened central Australian fauna
(Griffin 1993; Puckey and others 2007). It is also frequent
in restricted, sheltered micro-sites on cliffs and ledges
where it competes with rare and relict plant species and
alters fire regimes and the habitats of native flora and fauna
(Griffin 1993). The species can generate positive fire-
invasion feedbacks in central Australian woodlands (Miller
and others 2010) and affects fire regimes in Acacia cam-
bagei F.Muell. ex R.T.Baker (gidgee) and A. harpophylla
Benth. (brigalow) communities (Butler and Fairfax 2003).
Buffel grass has significant negative effects on plant spe-
cies richness (Grice and others 2004; Clarke and others
2005; Fairfax and Fensham 2000; Franks 2002; Jackson
2005; McIvor 1998) and some negative effects on partic-
ular fauna (Best 1998; Ludwig and others 2000; Eyre and
others 2009; Smyth and others 2009). It has been singled
out in assessments of threats to a number of native plants
and animals (Friedel and others 2006) and listed among
species of ‘‘extensive continental distribution’’ that are
‘‘capable of destroying’’ Australian ecosystems (Humphries
and others 1991).
In spite of assessments that buffel grass both provides
major economic benefits and poses significant environ-
mental threats, there is neither universal agreement about
the issues, nor open, mutual recognition by all stakeholders
of the costs and benefits. Rather, it has been the subject of
contrasting perspectives and conflicting opinions.
Strategic Options for the Management of Buffel Grass
In Australia there have been few attempts to address con-
tentious plant species in a strategic, broad-scale, systematic
way in order to simultaneously attract their benefits and
avoid or minimise their deleterious effects. Either no res-
olution to the contention is sought and no concerted action
is taken or the resolution favours one group of stakeholders
over others. Where no concerted action is taken, both
proponents and opponents are left to respond to their cir-
cumstances as individual land managers.
Where concerted action is taken it usually involves
prohibition of cultivation, as with gamba grass (Andropo-
gon gayanus Kunth) and Olive hymenachne (Hymenachne
amplexicaulis Nees) which have been declared to be pest
plants in some Australian states (Table 1). The legislation
of most Australian states overtly prohibits the cultivation of
plants that are formally recognised as pests though a
compromise has been attempted in the case of gamba grass
in the Northern Territory (Table 1).
Buffel grass has been listed among the ‘‘prohibited,
regulated and restricted noxious weeds’’ of Arizona, USA
(USDA 2011) but there has been little concerted action to
deal with its negative effects in Australia. It is not listed in
Fig. 1 Approximate current distribution of buffel grass in Australia
based on herbarium records. The locations of individual records from
Australian herbaria are shown (filled circle) (Australia’s Virtual
Herbarium 2010). The shaded area encompasses 90% of locations of
all herbarium records
286 Environmental Management (2012) 49:285–294
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the weed legislation of any Australian state, and there have
been no state-level and few regional-level attempts to
regulate sale, planting or spread of the species. Several
regional Natural Resource Management (NRM) bodies or
Catchment Management Authorities (e.g., South Australian
Arid Lands (SAAL), Western Australian Rangelands,
Northern Territory NRM) have identified buffel grass as
presenting important natural resource management issues
(Friedel and others 2006). Under its Pastoral Land Man-
agement and Conservation Act (1989) South Australia has
developed a policy to control non-indigenous plants on
leasehold pastoral lands and their introduction is not per-
mitted without written approval of the Pastoral Board that
is responsible for overseeing their management. Moreover,
the SAAL NRM Board has developed a Buffel Grass
Management Plan, its purpose being to identify priority
actions (Greenfield 2007). In South Australia, soils and
climate are probably less suitable for buffel grass than
those of other regions of Australia, so that historically there
has been less incentive to use it as a pasture species,
increased likelihood of legislative controls and less oppo-
sition to such legislation.
Failure to explore options other than unregulated use is
probably due to perceptions that it is technically and/or
economically difficult to control buffel grass on a practical
scale and that there would be overwhelming opposition to
using technical capacity that is available. Proponents have
often denied deleterious impacts of buffel grass (Marshall
and others 2011) and tend to attribute to the species greater
environmental benefits than do opponents (Friedel and
others 2011). Opponents have not fully acknowledged the
species’ value. Thus, proponents down-play the costs,
while opponents down-play the benefits. Government
agencies have long promoted the use of buffel grass and
other invasive forage species including leucaena Leucaena
leucocephala (Lam.) de Wit (Walton 2009), gamba grass
(Cameron and Lemcke 2006) and Olive hymenachne (Hall
2000).
Table 1 Legislative status of five important contentious pasture grasses in each State and Territory jurisdiction of Australia
State/Territory C. ciliaris A. gayanus H. amplexicaulis E. polystachya U. mutica
Australian Capital Territory
a
Not declared Not declared Declared class 4 Not declared Not declared
New South Wales
b
Not declared Not declared Declared class 1 Not declared Not declared
Northern Territory
c
Not declared Declared class A/C Declared class B/C Not declared Not declared
Declared class B/C
Queensland
d
Not declared Declared class 2 Declared class 2 Not declared Not declared
South Australia
e
Not declared Not declared Declared—control not required Not declared Not declared
Tasmania
f
Not declared Not declared Not declared Not declared Not declared
Victoria
g
Not declared Not declared Declared—restricted Not declared Not declared
Western Australia
h
Not declared Declared P1, P2 Declared P1, P2 Not declared Not declared
a
Australian Capital Territory: Class 4: Propagation and supply is prohibited
Source: http://www.tams/act.gov.au/_data/assets/pdf_file/0019/123706/Pest_Plants_and_Animals_Declaration_DI200844.pdf (accessed August
13 2009)
b
New South Wales Class 1: plant must be eradicated and the land must be kept free of the plant
Source: http://www.dpi.nsw.gov.au/agriculture/pests-weeds/weeds (accessed August 12 2009)
c
Northern Territory: Class A/C: plants to be eradicated/new entries prevented; Class B/C: growth and spread to be controlled/; Class C:
new entries prevented. For A. gayanus the Northern Territory is divided into a ‘‘Management Zone’’ (Class B/C) and an ‘‘Eradication Zone’’
(Class A/C)
Source: http://www.nt.gov.au/nreta/natres/weeds/legislation/declared.html (accessed August 12 2009)
d
Queensland Class 2: landholders must try to keep their land free of these plants and sale and supply are prohibited unless a permit is issued
Source: http://www.dpi.qld.gov.au/cps/rde/dpi/hs.xsl/4790_7024_ENA_HTML.htm (accessed August 12 2009)
e
South Australia: Class: control not required
http://www.dwlbc.sa.gov.au/biodiversity/apc/projects/weeds/plants_list.html
f
Tasmania: Source: http://www.dpiw.tas.gov.au/inter.nsf/WebPages/SSKA-73U3QA?open
g
Victoria: Restricted—cannot be traded as plants, seeds or contaminants
Source: Melville, R. Declared Noxious Weeds—Listed by Scientific Names. Landcare Notes (LC0252b), Department of Primary Industries,
Victoria. ISSN 1329-833X. http://www.dpi.vic.gov.au/DPI/nreninf.nsf/v/D7685D9BB33B4DB1CA25740A0011E32F/$file/Declared_Noxious_
Weeds_Listed_by_Scientific_Name.pdf (accessed August 13 2009)
h
Western Australia: P1: Movement of plants or seeds prohibited; P2: Infestations to be eradicated; spread of plants must be prevented
Source: http://www.agric.wa.gov.au/objwr/imported_assets/content/pw/weed/decp/dec_plants_lits.pdf (accessed August 13 2009)
Environmental Management (2012) 49:285–294 287
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Foundations for a Broad-Scale Buffel Grass Strategy
Given that buffel grass is already widespread and abundant
(Friedel and others 2006), northern and central Australian
pastoral industries are strongly dependent on it (Marshall
and others 2011) and there is likely to be resistance to any
restrictions on its use (Friedel and others 2011), it is
important to seriously consider whether broad-scale, stra-
tegic options, other than unfettered use, are viable and how
such options might be developed.
A broad-scale strategic approach to buffel grass would
aim to reduce deleterious effects without severely dimin-
ishing the species’ productive value. It would need to be
consultative, realistic in its goals, applicable at a range of
scales, responsive to regional differences, clear in its
allocations of responsibilities, supported by appropriate
legislative and non-legislative measures and based on
sound information.
Consultation
Broad consultation would be crucial to the development
and implementation of a national, strategic approach to the
management of any contentious species (Fraser and
Dougill 2006). A stakeholder-driven strategy is far more
likely to be effective than a top-down approach but it
would be naı
¨
ve to assume that consultation can provide
a ‘‘win-win’’ solution; compromise is a more realistic
expectation (Friedel and others 2011).
Consultation could be staged (Nelson and Pettit 2004).
Initial, broad engagement should increase the likelihood
that any subsequently developed strategy would be
socially, economically and politically acceptable. Later, an
advisory group incorporating stakeholder organisations
could help develop and implement the strategy. One of its
roles could be to progress toward consensus and compro-
mise amongst government agencies and catalyse more
productive approaches amongst stakeholders at large.
Proponents of buffel grass would be more vulnerable
than opponents to any changes from the status quo. Actions
designed to reduce the deleterious effects of buffel grass
could impose costs on proponents, whether they be reduced
production, increased production costs and opportunity
costs associated with development prospects that are
denied. Consultation will itself impose significant trans-
action costs.
Realistic Strategic Goals
Ideally, a strategy would include goals applicable at
national, state, regional and finer scales. They can be
logically grouped into four categories: prevention, eradi-
cation, containment and asset protection (Grice 2009).
Preventing introduction at the very broad (e.g., national
or continental) scale (Grice 2000) is no longer an option
but it may be useful to preclude new genetic material to
restrict the species’ capacity to occupy ‘new’ habitats. This
would involve a trade-off against the desirability of new
strains or ecotypes that could enhance the species’ value to
pastoralism in particular locations or management systems.
Risk assessment for new genetic material would be valu-
able though it is not currently required for species already
in Australia (Spafford-Jacob and others 2004).
While some introduced plants have been eradicated
from Australia (e.g., Dodd 2004; Rudman and Goninon
2002; Tomley and Panetta 2002) and other efforts are still
in progress (e.g., Brooks and Galway 2006; Csurhes 2004;
Mitchell and Schmid 2002; Warren 2006), continental-
scale eradication of buffel grass is neither possible nor
desirable. However, eradication at finer scales may be a
valid and achievable goal. Isolated populations of buffel
grass in vulnerable land types on high value conservation
reserves could be targeted for eradication, as could popu-
lations on off-shore islands, where the prospects of recol-
onisation are likely to be lower than on the mainland
(Dixon and others 2002). Following eradication it would be
necessary to monitor in order to promptly detect and
respond to further incursions (Holcombe and Stohlgren
2009). The frequency and location of monitoring should
respectively reflect the likelihood of recolonisation and the
routes whereby recolonisation is most likely.
Containment, that is imposing anthropogenic limits to a
species’ distribution (Grice 2009; Grice and others 2010),
is likely to be difficult for buffel grass because wind is a
major dispersal agent (Friedel and others 2006; CRCAWM
2008). Containment targets could be identified at a fine
scale, for example, small infestations on individual land-
units (e.g., conservation reserves; non-pastoral Aboriginal
lands). At the regional scale (e.g., parts of central Austra-
lian deserts) the goal could be to minimise range expansion
by targeting dispersal routes and mechanisms to counter
spread to areas that are currently free from the species.
Such areas would have to be identified and prioritised,
addressing the range of perspectives and needs in relation
to buffel grass, considering its costs and benefits in dif-
ferent regions. Perhaps the greatest challenge to the con-
tainment of buffel grass is that in most parts of Australia
where buffel grass is present there are multiple populations
and ecotypes (Friedel and others 2006). Cacho (2004), on
the basis of a conceptual model of weed spread that
included partial cost-benefit analysis, argued that in some
cases the optimum weed management strategy may be
‘partial containment’, that is slowing the rate of spread.
Cost-benefit analysis may help determine the value of
288 Environmental Management (2012) 49:285–294
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attempting to contain one local population in the face of the
risks posed by others (Buckley 2008).
Asset protection strategies would aim to minimise
impact of buffel grass by suppressing particular popula-
tions (Grice 2009), reducing its prevalence in terms of its
proportional contribution to total biomass or biomass of the
lower stratum of the vegetation, its density or the average
size of plants. This goal requires that specific assets and the
level of suppression necessary to protect them are identi-
fied. There has been little research on how buffel grass can
be suppressed but there is the experience of those who have
attempted to do so and several options have been canvassed
(Friedel and others 2011).
Each of these four broad strategic goals may be appro-
priate in different situations. Whether a goal is realistic in a
particular situation depends on there being the biophysical
means of achieving it, resources to make those means
operational and incentive on the part of stakeholders. For
contentious species the extent to which different goals can
be applied to different areas, without there being undue
interference between them, is important. A robust strategy
requires that actions taken at one location do not devalue
those applied to adjacent areas. Measures taken to reduce
negative environmental impacts should not unduly inter-
fere with the productive value of pastures, especially where
no realistic alternatives exist. In some situations this would
require relatively fine-scale spatial separation of areas
targeted for different strategic goals.
Scale
A continental (national)-scale strategy would provide a
context in which regional (State or large catchments) ele-
ments might be framed. National recognition of the issues
should facilitate interstate collaboration and co-ordination,
yield economies of scale and improve access to Com-
monwealth resources (e.g., to support research). A national
strategy may help attract the necessary involvement of
national organisations (Commonwealth government
departments and agencies; non-governmental organisa-
tions). Many of the actions required to make a national
strategy effective would actually be implemented at finer
scales in a hierarchical way. For example, a national
strategy would require the backing of state legislation that
should also reflect nuances in need at finer scales.
Regional Responsiveness
A strategy should reflect inter-regional differences in
physical, social and economic environments. These include:
the contributions that buffel grass makes to pastoral
production; the ways in which it is managed; the environ-
mental services it provides; its extent; the impacts it has on
native flora and fauna; its status under legislation; and the
suitability and effectiveness of the measures available
(Marshall and others 2011; Friedel and others 2011).
Current projects managing buffel grass reflect the need
for and validity of different responses in different areas.
For example, at the very finest scale, a 54 ha area of the
Alice Springs Desert Park has been the target of a buffel
grass control program that has, since 1996, reduced the
species to very low abundance, the ultimate goal being
local eradication (CRCAWM 2008). Programs to control
buffel grass have also been implemented on conservation
reserves such as Uluru-Kata Tjuta National Park in central
Australia (Anon 2009). These actions aim to alleviate
perceived or demonstrated impacts at sites with high con-
servation values. The regional-scale strategic plan for
buffel grass for the SAAL (Greenfield 2007) reflects how
the status of buffel grass in that region differs from its
standing elsewhere.
Allocation and Acceptance of Responsibilities
In Australia, local, state and Commonwealth governments
have responsibilities in weed management and national
strategies have been developed for Australia’s twenty Weeds
of National Significance (WONS) under a Commonwealth-
State initiative (ARMCANZ 1999; Martin and van Klinken
2006). Some of these have had to address divergent views
among stakeholders [e.g., Olive hymenachne (CRCAWM
2003a); willows Salix spp. (CRCAWM 2003b)] though the
contentions were not as extreme as those associated with
buffel grass. However, in all of these cases, actions taken
under the agreement between Commonwealth and State
governments have emphasised, to the virtual total exclusion
of other possibilities, the costs associated with the plants’
impacts, precluding exploitation. For buffel grass, regulation
and co-ordination might be more effective if it was con-
ducted outside the conventional pest plant arena, including
Australia’s National Weeds Strategy (ARMCANZ 1999),
thus more clearly acknowledging the species’ economic
values. A national strategy would also need to consider
responsibilities of local government and individual land-
holders.
Legislative and Non-Legislative Measures
Strategic management of any contentious plant species
requires an appropriate legislative framework and balance
between legislative and non-legislative measures. In Aus-
tralia’s Northern Territory there has been some move away
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from ‘‘watershed’’ decisions based on typical pest plant
legislation. A draft Weed Management Plan for Gamba
Grass (NRETAS 2009) delineates a ‘‘management zone’’,
in which the aim is to ‘‘[contain] established pasture areas
(e.g., through the use of grazing land management princi-
ples and the maintenance of buffer zones)’’ and an ‘‘eradi-
cation zone’’. However, there are no legislative measures to
deal with most other contentious pasture grasses (Table 1).
Non-legislative measures could play an important role
but would require broad stakeholder consultation during
both development and implementation. Non-legislative
elements may encourage consensus and/or compromise
(Walton 2004) and could include voluntary codes of
practice (Walton 2009), insurance mechanisms (Martin
2008) and certification procedures related to off-site
impacts. Valid Australian precedents address species that
are potential sources of illicit drugs (e.g., poppies in Tas-
mania (Department of Justice 2010); Indian hemp in New
South Wales (Zurbo 2008)), which present many of the
same issues as invasive pasture species.
The code of practice for leucaena (Walton 2009) pro-
vides a precedent though there are currently no reliable
assessments of its effectiveness. Leucaena and buffel grass
are both important, extensively cultivated forage species in
northern Australia but a code of practice for buffel would
have to be tailored for it (Grice 2006). Leucaena is most
useful when grown in horticultural-style plantations in
which self-propagation is unnecessary; the use of leucaena
lends itself to the use of sterile varieties and containment of
plantings may be relatively straight-forward. Exploitation
of buffel grass, on the other hand, depends strongly on its
free-seeding characteristics and its capacity to self-propa-
gate in extensively managed areas. A code of practice
would also have to address issues of non-compliance and
the pre-existence of extensive naturalised populations.
Specific Practical Elements
Marshall and others (2011) concluded that pastoralists in
three out of four divergent regions of Australian rangelands
are strongly dependent on buffel grass. Generally, they do
not accept that buffel grass has negative environmental
consequences but are supportive, at least in principle, of
efforts to control buffel grass on conservation reserves.
Studying the same four regions, Friedel and others (2011)
concluded that the contention amongst diverse organisa-
tions was not as great as might have been supposed: benefits
and costs of buffel grass were widely acknowledged; there
was general agreement in relation to management objec-
tives for environmental reserves and pastoral lands of low
conservation value. However, the objectives for pastoral
lands of high conservation value were contentious. A
variety of management tools and strategies were broadly
supported, with exceptions that could be explained largely
in terms of regional differences in ability to apply them.
A national approach could initially respond to these
perceptions by focusing on practical elements that relate to
the less contentious, relatively straightforward aspects.
Clearly, their effectiveness would depend on adequate
resourcing (expertise and funding). Possible actions
include the following.
Avoid Development, Movement and Introduction
or Release of New Varieties
Preventing the introduction, movement or development of
new buffel grass varieties could help minimise further
range expansion. Buffel grass varieties that are more cold-
tolerant or capable of growing well on clay soils, for
example, could increase the species’ potential distribution.
Avoiding the introduction of new varieties may also reduce
the development, through mutation and/or hybridisation of
genotypes that are better adapted to particular environ-
ments. Adaptation could involve natural selection for less
palatable genotypes and countering such selection might be
difficult in practice. Restrictions on the introduction of new
varieties could impose opportunity costs on proponents of
the species.
Identify Regions Where Buffel Grass is Sparse
and Counter Its Proliferation
Containment could be a valid and acceptable goal for
populations of buffel grass in the extensive areas of central
and southern Australia where it is relatively sparse, where
pastoralism is not a significant land-use and where there are
important land values that could be compromised should
the species increase. There are large conservation reserves
and non-pastoral Aboriginal lands in Western Australia, the
Northern Territory, Queensland and South Australia. The
absence of buffel grass from these lands would not detract
from pastoral production and may enhance their value for
conservation and indigenous people. Effort would focus on
the routes whereby buffel grass is likely to spread, princi-
pally transport corridors, and managing plant communities
to be more resistant to invasion.
Keep Buffel Grass Out of Conservation Reserves
Where It is Absent or Sparse
Because livestock grazing is prohibited on most Australian
conservation reserves, buffel grass could be excluded,
contained or suppressed without compromising pastoral
production. Priority should be given to conservation
reserves where (i) buffel grass is rare or absent and yet
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there is a significant risk of incursion and; (ii) important
natural assets are or would be threatened by an abundance
of buffel grass.
Negotiate Compromise Solutions for Biodiverse Areas
Outside Conservation Reserves
In Australia, many areas outside conservation reserves
have considerable environmental value, particularly in the
extensive rangelands (Smyth and James 2004). They
present the greatest challenge to broad-scale, strategic
management of buffel grass. It is crucial to understand how
the abundance and distribution of buffel grass affects
conservation values in biodiverse landscapes. Financial
compensation for any losses to productive capacity, or
some other incentive scheme, may be appropriate for areas
of high conservation value.
Contain Strategically Located Populations of Buffel
Grass That Cannot be Eradicated
If there are isolated but important plantings of buffel grass
in regions where buffel grass is not otherwise widespread
and abundant, effort could be made to contain them though
containment of free-seeding species presents a major
challenge (Grice and others 2010).
Focus Control on the Most Detrimental Varieties
of Buffel Grass
In Australia, genetic and environmental factors drive con-
siderable variation in how palatable buffel grass is to
livestock. It would be valuable to ascertain how the dif-
ferent varieties relate to one another, their comparative
distributions, the scales at which they co-occur and their
relative advantages and disadvantages for animal produc-
tion and the environment. This knowledge could be used to
determine whether it is likely to be worthwhile specifically
targeting less palatable varieties of buffel grass for sup-
pression or containment. The situation is complicated by
the fact that different varieties are more suitable for pas-
toralism in different regions (Friedel and others 2006).
Need for Further Information
A strategy for dealing with buffel grass requires better
information in the following areas.
Environmental Impacts
Better quantification of the environmental impacts of buffel
grass in different situations and geographical areas would
link both production benefits and conservation outcomes to
the abundance of buffel grass. A better understanding of
the ecological processes involved would help prioritise
between locations and identify environmental values that
are at greatest risk.
Cost-Benefit Analysis
Sound cost-benefit analysis is required. A major challenge
here is to weigh the many costs and benefits that are typ-
ically expressed in very different currencies, expanding on
the work that has been done to date (e.g., Chudleigh and
Bramwell 1996; Ferdinands and others 2010). For con-
tentious species in general, cost-benefit analysis could be
used to help decide between broad strategic options: no
regulation of the species; prohibition of cultivation and a
requirement for control through weeds legislation; or a
compromise approach that seeks to attract benefits from
cultivation whilst avoiding costs associated with invasion.
More discerning cost-benefit analysis would be required to
develop regionally differentiated goals.
Management Options
There is a need for better knowledge of how buffel grass
can be best managed for different purposes. Friedel and
others (2011) tabulated management tools potentially
applicable to buffel grass. Numerous land managers hold
knowledge of how grazing, fire, herbicides and other
techniques may or may not be applicable in different sit-
uations. There would be value in capturing this informa-
tion, combining it with the results of more formal testing
and using it to refine ‘‘best bet’’ management practice for
different goals and circumstances.
Distribution and Abundance
Higher resolution spatial data on the current and potential
distribution and abundance of buffel grass would facilitate
a more targeted approach to setting spatial priorities and in
determining what is achievable.
Intra-Specific Variation
It would be useful to quantify and map the variation that
exists in the buffel grasses currently present in Australia.
Current information suggests that registered cultivars are
not readily distinguishable amongst the genotypic and
phenotypic variety that exists in the field but also that for
both proponents and opponents of the species there are
more and less desirable varieties (Friedel and others 2006).
In documenting existing variation it would be important to
align it with invasiveness and its usefulness as a pasture
Environmental Management (2012) 49:285–294 291
123

plant. It is likely that the geographical variation in the form
and function of buffel grass in Australia is a product of
some combination of environmental and genetic factors.
Conclusions
As is often the case with contentious plant species, little
effort has been made to resolve conflicting perspectives
toward buffel grass in Australia. However, there is sufficient
common ground between interest groups to encourage res-
olution and development of a systematic, co-ordinated and
consultative approach to the species. The geographical focus
should be on regions where buffel grass is currently scarce or
not present and on specific locations whose high conserva-
tion value is threatened by invasion of buffel grass. There is
scope for the sharing of practical knowledge between
stakeholders who hold divergent views. The approach that
we advocate for buffel grass should be broadly applicable to
other contentious, invasive plant species.
Acknowledgments We acknowledge the contributions of partici-
pants in workshops that were part of a research project funded
through Land and Water Australia (Project LWA-DWM CSE52).
Judy Lambert and other Land and Water Australia personnel were
instrumental in maximising the benefits of this work. Brett Abbott
created the map. We thank Andrew Ash, Silva Larsen and three
anonymous referees for their helpful comments on a draft manuscript
of this paper.
References
Anon. (2009) Uluru-Kata Tjuta National Park, Draft Management
Plan 2009–2019. Director of National Parks, Australian Gov-
ernment, Canberra. Accessed online January 14, 2011: http://
www.environment.gov.au/parks/publications/uluru/pubs/draftplan.
pdf
ARMCANZ (Agriculture and Resource Management Council),
ANZECC (Australian and New Zealand Environment and
Conservation Council) and FM (Forestry Ministers) (1999) The
National Weeds Strategy (Revised Edition). Commonwealth of
Australia, Canberra
Australia’s Virtual Herbarium (2010) Cenchrus ciliaris. Accessed
online February 19, 2010: http://www.anbg.gov.au/avh/cgi-bin/
avh.cgi
Best RA (1998) The effect of introduced buffel grass (Cenchrus
ciliaris L., Poaceae) on the diversity and abundance of inver-
tebrates in semi-arid central Australia. Masters Thesis, Northern
Territory University, Darwin
Brooks SJ, Galway KE (2006) Progress towards the eradication of
two tropical weeds. In: Preston C, Watts JH, Crossman ND (eds)
Proceedings of the 15th Australian Weeds Conference. Weed
Management Society of South Australia, Adelaide, pp 641–644
Buckley YM (2008) The role of research for integrated management
of invasive species, invaded landscapes and communities.
Journal of Applied Ecology 45:397–402
Butler DW, Fairfax RJ (2003) Buffel grass and fire in a gidgee and
brigalow woodland; a case study from central Queensland.
Ecological Management and Restoration 4:120–125
Cacho O (2004) When is it optimal to eradicate a weed invasion? In:
Sindel BM, Johnson SB (eds) Proceedings of the 14th Australian
Weeds Conference. Weed Society of New South Wales, Sydney,
pp 49–54
Cameron AG and Lemcke B (2006) Kent Gamba Grass. Agnote E8,
Serial No. 413, Agdex No. 131/10. Department of Primary
Industry, Fisheries and Mines, Northern Territory Government.
Accessed online January 18 2011. www.nt.gov.au/dpifm
Chudleigh P, Bramwell T (1996) Assessing the impact of introduced
tropical pasture plants in northern Australia. Report to CSIRO
taskforce interested in introduced pasture plants. March 11 1996
Clarke PJ, Latz PK, Albrecht DE (2005) Long-term changes in semi-
arid vegetation: Invasion of an exotic perennial grass has larger
effects than rainfall variability. Journal of Vegetation Science
16:237–248
Cook GD, Dias L (2006) It was no accident: deliberate plant
introductions by Australian government agencies during the
twentieth century. Australian Journal of Botany 54:601–625
CRCAWM (Co-operative Research Centre for Australian Weed
Management) (2003a) Weed Management Guide: Hymenachne
(Hymenachne amplexicaulis). CRC Australian Weed Manage-
ment, Adelaide
CRCAWM (Co-operative Research Centre for Australian Weed
Management) (2003b) Weed Management Guide: Willows
(Salix spp.). CRC Australian Weed Management, Adelaide
CRCAWM (Co-operative Research Centre for Australian Weed
Management) (2008) Weed Management Guide: Buffel grass
(Cenchrus ciliaris). CRC Australian Weed Management,
Adelaide
Csurhes SM (2004) Succesful control of honey locust trees (Gleditsia
triacanthos L.) in Queensland. In: Sindel BM, Johnson SB (eds)
Proceedings of the 14th Australian Weeds Conference. Weed
Society of New South Wales, Sydney, pp 673–675
Department of Justice (2010) Poppy advisory and control board
(Tasmania). Accessed online January 18, 2011. http://www.
justice.tas.gov.au/poppy/
Dixon IR, Dixon KW, Barrett M (2002) Eradication of buffel grass
(Cenchrus ciliaris) on Airlie Island, Pilbara Coast, Western
Australia. In: Veitch CR, Clout MN (eds) Turning the tide: the
eradication of invasive species. IUCN SSC Invasive Species
Specialist Group. IUCN, Gland, Switzerland and Cambridge,
pp 92–101
Dodd J (2004) Kochia (Bassia scoparia (L.) A.J. Scott eradication in
Western Australia: a review. In: Sindel BM, Johnson SB (eds)
Proceedings of the 14th Australian Weeds Conference. Weed
Society of New South Wales, Sydney, pp 496–499
Eyre TJ, Wang J, Venz MF, Chilcott C, Whish G (2009) Buffel grass
in Queensland’s semi-arid woodlands: response to local and
landscape scale variables, and relationship with grass, forb and
reptile species. The Rangeland Journal 31:293–305
Fairfax RJ, Fensham RJ (2000) The effect of exotic pasture
development on floristic diversity in central Queensland, Aus-
tralia. Biological Conservation 94:11–21
Ferdinands KB, Setterfield SA, Clarkson JR, Grice AC, Friedel MH
(2010) Embedding economics in weed risk assessment to assess
contentious plants. In: Zydenbos SM (ed) Proceedings of the
17th Australasian Weeds Conference. New Zealand Plant
Protection Society, Christchurch, pp 482–485
Franks AJ (2002) The ecological consequences of buffel grass
Cenchrus ciliaris establishment within remnant vegetation of
Queensland. Pacific Conservation Biology 8:99–107
Fraser ED, Dougill AJ (2006) Bottom up and top down: analysis of
participatory processes for sustainability indicator identification
as a pathway to community empowerment and sustainable
environmental management. Journal Environmental Manage-
ment 78:114–127
292 Environmental Management (2012) 49:285–294
123

Friedel M, Puckey H, O’Malley C, Waycott M, Smyth A, Miller G
(2006) Buffel grass: both friend and foe. An evaluation of the
advantages and disadvantages of buffel grass use and recom-
mendations for future research. Desert Knowledge Cooperative
Research Centre, Alice Springs. http://www.desertknowledgecrc.
com.au/resource/DKCRC-Report-17-Buffel-Grass.pdf (Acces-
sed 23 May 2011)
Friedel MH, Grice AC, Marshall NA, van Klinken RD (2011)
Reducing contention amongst organisations dealing with com-
mercially valuable but invasive plants: the case of buffel grass.
Environmental Science and Policy. doi:10.1016/j.envsci.2011.
08.001
Greenfield B (2007) SA Arid Lands buffel grass management plan,
DRAFT. South Australian Arid Lands Natural Resource Man-
agement Board, Port Augusta
Grice AC (2000) Weed management in rangelands. In: Sindel BM
(ed) Australian weed management systems. RG and FJ Rich-
ardson, Meredith, pp 431–458
Grice AC (2004) Perennial grass weeds in Australia: impacts,
conflicts of interest and management issues. Plant Protection
Quarterly 19:42–47
Grice AC (2006) Commercially valuable weeds: can we eat our cake
without choking on it. Ecological Management and Restoration
7:40–44
Grice AC (2009) Principles of containment and control of invasive
species. In: Clout MN, Williams PA (eds) Invasive species
management: a handbook of principles and techniques. Oxford
University Press, Oxford, pp 61–76
Grice AC, Field AR, McFadyen REC (2004) Quantifying the effects
of weeds on biodiversity: beyond Blind Freddy’s test. In: Sindel
BM, Johnson SB (eds) Proceedings of the 14th Australian Weeds
Conference. Weed Management, Balancing People, Planet,
Profit; Wagga Wagga. Weed Society of New South Wales,
Sydney, pp 464–468
Grice AC, Clarkson J, Spafford H (2008) Commercial weeds: roles,
responsibilities and innovations. Plant Protection Quarterly
23:58–64
Grice AC, Clarkson JR, Friedel MH, Ferdinands K, Setterfield S.
2010. Containment as a strategy for tackling contentious plants.
In: Zydenbos, SM (ed) Proceedings of the 17th Australasian
Weeds Conference. New Zealand Plant Protection Society,
pp 486–489
Griffin GF (1993) The spread of buffel grass in inland Australia: land
use conflicts. In: Proceedings of the 10th Australian Weeds
Conference and the 14th Asian Pacific Weed Science Society
Conference. Weed Society of Queensland, Brisbane, pp 501–504
Hall TJ (2000) History and development of buffel grass pasture lands
in Queensland. In: Cook B (ed) Proceedings of buffel grass
workshop, Theodore Qld, 21–23 February 2000, Department of
Primary Industries, Queensland, pp 2–12
Holcombe T, Stohlgren TJ (2009) Detection and early warning of
invasive species. In: Clout MN, Williams PA (eds) Invasive
species management: a handbook of principles and techniques.
Oxford University Press, Oxford, pp 36–46
Humphreys LR (1967) Buffel grass (Cenchrus ciliaris) in Australia.
Tropical Grasslands 1:123–134
Humphries SE, Groves RH, Mitchell DS (1991) Plants invasions of
Australian ecosystems: a status review and management direc-
tions. Kowari 2:1–116
Jackson J (2005) Is there a relationship between herbaceous species
richness and buffel grass (Cenchrus ciliaris)? Austral Ecology
30:505–517
Keetch RI (1981) Rangeland rehabilitation in Central Australia. Alice
Springs, Conservation Commission of the Northern Territory,
Darwin
Lawson BE, Bryant MJ, Franks AJ (2004) Assessing the potential
distribution of buffel grass (Cenchrus ciliaris L.) in Australia
using a climate-soil model. Plant Protection Quarterly 19:
155–163
Lonsdale WM (1994) Inviting trouble: introduced pasture species in
northern Australia. Australian Journal of Ecology 19:345–354
Ludwig JA, Eager RW, Liedloff AC, McCosker JC, Hannah D,
Thurgate NY, Woinarski JCZ, Catterall CP (2000) Clearing and
grazing impacts on vegetation patch structures and fauna counts
in eucalypt woodland, Central Queensland. Pacific Conservation
Biology 6:254–272
Marshall NA, Friedel M, van Klinken RD, Grice AC (2011)
Considering the social dimensions of contentious species: the
case of buffel grass. Environmental Science and Policy 14(3):
327–338
Martin P (2008) Cross pollination or cross-contamination? Directions
for informing the management of invasives with market-
economy concepts. In: van Klinken RD, Osten VA, Panetta
FD, Scanlan JC (eds) Proceedings of the 16th Australian Weeds
Conference. Queensland Weeds Society, Brisbane, pp 6–13
Martin TG, van Klinken RD (2006) Value for money? Investment in
weed management in Australian rangelands. The Rangeland
Journal 28:63–75
McIvor J (1998) Pasture management in semi-arid tropical wood-
lands: effects on species diversity. Australian Journal of Ecology
23:349–364
Miller G, Friedel M, Adam P, Chewings V (2010) Ecological impacts
of buffel grass (Cenchrus ciliaris L.) invasion in central
Australia: does field evidence support a fire-invasion feedback?
The Rangeland Journal 32:353–365
Mitchell A, Schmid M (2002) Case history of the eradication of
fringed spider flower, Cleome rutidosperma DC. In: Spafford-
Jacob H, Dodd J, Moore, JH (eds) Proceedings of the 13th
Australian Weeds Conference. Plant Protection Society of
Western Australia, Perth, pp 297–299
Nelson AL, Pettit C (2004) Effective community engagement for
sustainability: wombat community forest management case
study. Australian Geographer 35:301–315
NRETAS (Department of Natural Resources, Environment, The Arts
and Sport) (2009) Weed Management Plan for Gamba Grass
(Andropogon gayanus) August 2009. Northern Territory Gov-
ernment, Palmerston. Accessed online January 18 2011: http://
www.nt.gov.au/nreta/natres/weeds/find/gamba/pdf/draft_weedmg
mtplan.pdf
Puckey H, Brock C, Yates C (2007) Improving the landscape scale
management of buffel grass Cenchrus ciliaris using aerial
survey, predictive modelling, and a Geographic Information
System. Pacific Conservation Biology 13:264–273
Rudman T, Goninon C (2002) Eradication case history, Hieracium
pilosella L. ssp. nigrescens (Fr.) Na
¨
geli & Peter in Tasmania. In:
Spafford-Jacob H, Dodd J, Moore JH (eds), Proceedings of the
13th Australian Weeds Conference. Plant Protection Society of
Western Australia, Perth, pp 304–306
Smyth AK, James CD (2004) Characteristics of Australia’s range-
lands and key design issues for monitoring biodiversity. Austral
Ecology 29:3–15
Smyth A, Friedel M, O’Malley C (2009) The influence of buffel grass
(Cenchrus ciliaris) on biodiversity in an arid Australian land-
scape. The Rangeland Journal 31:307–320
Spafford-Jacob H, Randall RP, Lloyd SG, King C (2004) Quarantine
law loophole: an examination of the known weed species
permitted for import without weed risk assessment. In: Sindel
BM, Johnson SB (eds), Proceedings of the 14th Australian
Weeds Conference. Weed Society of New South Wales, Sydney,
pp 684–689
Environmental Management (2012) 49:285–294 293
123

Tomley AJ, Panetta FD (2002) Eradication of the exotic weeds
Helenium amarum (Rafin) H.L. and Eupatorium serotinium
Michx. from south-eastern Queensland. In: Spafford-Jacob H,
Dodd J, Moore JH (eds), Proceedings of the 13th Australian
Weeds Conference. Plant Protection Society of Western Austra-
lia, Perth, pp 293–296
USDA (United States Department of Agriculture), Natural Resource
Conservation Service (2011) NRCS Invasive Species Policy,
Invasive Species Executive Order 13112. http://plants.usda.gov/
java/noxious?rptType=State&statefips=04 (Accessed 14 October
2011)
van Klinken RD, Panetta ED, Ross B, Wilson C (2004) A pain in the
grass: what’s the diagnosis? In: Sindel BM and Johnson SB
(eds), Proceedings of the 14th Australian Weeds Conference.
Weed Society of New South Wales, Sydney, pp 480–483
Walton C (2004) To declare or not to declare? That is the question. In:
Sindel BM, Johnson SB (eds), Proceedings of the 14th
Australian Weeds Conference. Weed Society of New South
Wales, Sydney, pp 62–67
Walton C (2009) Leucaena leucocephala (Lam.) de Wit. In: Panetta
FD (ed) The biology of Australian weeds, vol 3. RG and RF
Richardson, Melbourne, pp 143–156
Warren P (2006) The branched broomrape eradication program in
Australia. In: Preston C, Watts JH, Crossman ND (eds),
Proceedings of the 15th Australian Weeds Conference. Weed
Management Society of South Australia, Adelaide, pp 610–613
Zurbo B (2008). Growing low THC hemp under licence in NSW –
frequently asked questions. Primefact 841. NSW DPI. Accessed
online January 18 2011: http://www.dpi.nsw.gov.au/__data/
assets/pdf_file/0003/255225/Growing-low-thc-hemp-in-NSW-
faq.pdf
294 Environmental Management (2012) 49:285–294
123