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52 Rwanda Journal, Series E: Agricultural Sciences Vol. 1 No. 1, 2013
Rwanda Journal ISSN 2305-2678 (Print); ISSN 2305-5944 (Online)
DOI : http://dx.doi.org/10.4314/rj.v1i1.4E
Investigation of survival rate of trees planted in
agroforestry and forest plantations in HuyeDistrict from
2007 to 2011 and underlying factors
J. P. Murekezi, J. Nduwamungu and E. Munyanziza
Faculty of Agriculture,
National University of Rwanda
Corresponding Author: jnduwamungu@nur.ac.rw/jeanduwa@gmail.com
Abstract
This study was conducted in Huye District from December 2011 to June
2012, with aiming to investigate the survival rate of trees planted on private
and public land from 2007-2011 and underlying factors. Low survival rate of
trees planted during annual planting campaigns is often reported in many
parts of the country and there is need to understand why and propose
adequate solutions to improve survival rate of trees in plantation. The study
was conducted in three sectors of Huye District namely Mukura, Tumba and
Ngoma sectors. Data were collected through a structured questionnaire that
was administered to 51 sample farmers as well as through actual counts
conducted both on private and public trees and forest plantations. The
collected data were analysed and presented using SPSS and Microsoft Excel
softwares. The results of the study revealed that, in the study area, the
majority of trees fail to survive after the tree planting season generally due
to lack or poor post-planting care. Thirty nine percent of respondents
reported to have not provided any post-planting care to their trees.
Nevertheless, 35% of respondents reported to have weeded their trees during
the studied period. In addition, the results indicate that private trees survive
better than public ones. The mean survival rate computed on a sample of
agroforestry private trees was 51% while on public trees it was 30%. In
woodlots and forest plantations, private trees survived at 65% while the
public ones survived at 40%. This study should be carried out in other parts
of the country in order to identify underlying factors behind low survival rate
of trees after each tree planting season.
Keywords: Deforestation, reforestation, tree survival rate, tree planting
seasoning, physical count of trees.
Rwanda Journal, Series E: Agricultural Sciences Vol. 1 No. 1, 2013 53
1. Introduction
Deforestation has been going on in Rwanda since long time as forests
were cleared in favour of agriculture. However, during the last fifty
years, deforestation and forest degradation accelerated due to various
factors. Between 1960 and 2002, the area of natural forests of Rwanda
underwent a decrease of about 65% (Twagiramungu, 2006). The
search for arable lands, extensive farming, illegal felling of forests for
firewood, production of wood for charcoal and poles for building in
urban areas, as well as a land mismanagement have drastically
contributed to this reduction of natural forest coverage. Currently the
remaining natural forests are all protected and practically almost all
forest products needs are met through harvesting planted trees and
forests (ROR, 2010).
Nowadays, forest restoration is being addressed at the national and
international levels to restore previously depleted forests through
forest plantation establishment projects (Maginnis and Jackson, 2003;
Evans and Turnball, 2004). In Rwanda, every year, the government
with the support of various NGOs and development project donors,
spends a huge budget in forest restoration and rehabilitation through
production and distribution of tree seedlings throughout the country
(Nduwamungu, 2011). However, despite the great efforts invested in
mobilizing human and financial resources for tree planting during the
annual tree planting week and beyond, low survival rate of newly
planted trees and forests has been reported throughout the country
(ROR, 2010).Low survival rate of trees planted during community
works is common in many parts of the country and there is need to
understand why and propose adequate solutions to improve survival
rate of trees in reforested areas.
Huye District is one of the districts in which the issue of poor
establishment of newly planted trees has been widely observed as
indicated by the dominance of old forest plantations throughout the
District in comparison with the number of tree seedlings produced and
planted each year (HDESA, 2011). Thus, the objective of this study
was to investigate possible factors behind low survival rate of trees
after each tree planting season in Huye District and propose how to
54 Rwanda Journal, Series E: Agricultural Sciences Vol. 1 No. 1, 2013
ensure optimum establishment of man-made forests and agroforestry
trees.
2. Materials and Methods
This study was conducted within three sample sectors of Huye District
namely,Tumba, Ngoma and Mukura. In each sample sector, seventeen
respondents were randomly selected provided that they have planted
some trees between 2007 and 2011. A structured questionnaire
consisting of both open-ended and closed-ended questions was
prepared for data collection and was administered directly to 51
respondents while collecting also data on private trees and forests.
During interview, the questions asked focussed on total number of
trees planted by the respondent from 2007 to 2011(the species planted,
the type and source of planting materials, number that survived) and
on information about underlying factors that could influence the rate
of survival of newly planted trees such as tree planting method, tree
planting season, types and quality of seedlings used while planting,
aftercare activities done, seedling transportation method and handling,
control and monitoring of the planted trees.In addition, actual physical
count of surviving trees was carried out in randomly selected private
and public sites in the study area.
The physical count enabled estimation of the actual number of
surviving trees out of many planted either on private or public sites.
Through this count, each tree (s) reported to have been planted at any
site by each respondent was physically checked in order to ascertain
that the said trees were really planted and thereby being able to record
the reliable survival rate of trees on that site. Physical count also
helped identify the real species of the planted trees since some
respondents were not aware of tree species that were planted. Per each
site, only five transects were randomly selected for physical count, and
per each selected transect, both the number of empty holes and the
number of surviving trees were recorded. These records helped in
calculating the survival rate of trees per that site given that the total
number of planted trees was known. Figure1 is a sketch of how
physical count was carried out in the field. The Statistical Package for
Social Sciences (SPSS) and Microsoft Excel were used to process the
data.
Rwanda Journal, Series E: Agricultural Sciences Vol. 1 No. 1, 2013 55
Figure1: Graphical illustration of how physical count
was carried out in the field
Where: Lis length of the site,W is width of the site, isempty hole;
is surviving tree and T1, T2,…. T5are Transect numbers.
3. Results and Discussion
Source of tree planting stocks
All respondents reported that they use seedlings as the main tree
planting material. About 82% of respondents (Table 1) confirmed that
they use tree seedlings sourced from tree nurseries of administrative
Cells (“Pepiniyeriz’utugari”), suggesting that within Huye District,
seedlings distribution to the farmers generally occurs at the cell level.
Table 1: Source of tree planting stock
Source of planting stock
Frequency
(%)
Cell nursery
42
82.4
Sector nursery
4
7.8
Private nursery
3
6.0
Own nursery
1
2.0
Wildings
1
2.0
Tree planting period and techniques
About 82% of respondents reported that they planted their trees in
November which is the normal tree planting season. The greatest
proportion reported to dig planting pits one week before planting
(Table 2).Unless the pits are not deep enough this period is normally
56 Rwanda Journal, Series E: Agricultural Sciences Vol. 1 No. 1, 2013
about the right time to plant trees(the best being two weeks before
planting) (Nduwamungu, 2011). Nevertheless, it was reported that
seedlings are often transported by hands on open environment without
taking into account of potential sun heat damage which can increase
water loss by seedlings especially root desiccation (Landis and Haase,
2008) and later reduce survival rate of planted trees.
Table 2: Time of digging planting pits (N=51)
Time of digging
Frequency
Percentage (%)
The same day at the planting
period
10
19.6
A day before planting
4
7.8
Two days before planting
6
11.8
A week before planting
17
33.3
Two weeks before planting
8
15.7
More than two weeks before
planting
6
11.8
Post planting care conducted on newly planted trees
The majority of respondents (39%) reported that they do no post-
planting care to their trees. The trees are left on their own. Even
though 35% of farmers said that they carried out weeding, this
percentage is still at the lower end because weeding activity for tender
trees is known to be the most important post-planting care for
successful establishment of newly planted trees (Elefritzet al., 1998).In
fact, about 94% of respondents complained that after planting there is
no follow up of private trees and woodlots by forestry professionals in
the district. The care is all left to the farmer who is not even instructed
on proper tending techniques of young tree plantations. This is a great
challenge that should really be addressed if higher survival rate and
performance are to be achieved. Table 3summarises responses on the
follow up care provided to tender trees just after they are planted out.
Rwanda Journal, Series E: Agricultural Sciences Vol. 1 No. 1, 2013 57
Table 3: Post planting care conducted (N=51)
Type of care
Frequency
Percentage (%)
Nothing
20
39.2
Weeding
18
35.3
Watering during drought season
6
11.8
Fencing/sheltering
2
3.9
Low pruning
3
5.9
Mulching
1
2.0
Beating up
1
2.0
Annual survival rate of trees from 2007 to 2011
The results of this study indicated that there is still a great amount of
trees which fail to establish just after they are planted out. This is
proved by the relatively low survival rates of many trees planted either
on private land or on public land (Figures 2, 3, 4 &5). Nevertheless,
comparing the survival rates on private and public lands, it was noted
that trees on private lands survive better than those planted on public
lands. In fact, basing the actual physical count in sample agroforestry
and forest plantation sites randomly selected in the study area, the
mean survival rate during the last five years (2007-2011) in
agroforestry on private lands was 51% while on public lands it was
30%. In woodlots and forest plantations, trees on private lands
survived at 65% while those on public lands survived at 40% (Figures
4 &5).
58 Rwanda Journal, Series E: Agricultural Sciences Vol. 1 No. 1, 2013
Rwanda Journal, Series E: Agricultural Sciences Vol. 1 No. 1, 2013 59
The difference in survival rates on private and public lands may
probably be attributed to inappropriate handling methods of seedlings
while planting. Foster and Blaine (1978) remarked that one tree
planting contractor lost 38% of sidewalks trees in Boston City in the
first year due to careless handling of plant material. Poor survival may
have resulted also from insufficient control and monitoring as well as
insufficient post planting care provided to the public trees on different
planting sites. This is because most public trees and forest plantations
are generally established during community works known as
“Umugandarusange”. Even when some post-planting care activities
are undertaken on public lands, they are not properly done because
60 Rwanda Journal, Series E: Agricultural Sciences Vol. 1 No. 1, 2013
they are done during those community works by unskilled people
often without any guidance from forestry professionals
(Hategekimana, Forest extension officer, Pers. Communication).
4. Conclusion
This study has shown that a great number of trees fail to develop
properly after each tree planting season which results in poor
establishment of new forests in Huye District. Poor tree survival rate is
generally attributed topoor post-planting care whereby 39% of
respondents reported that they do not provide any post-planting care to
their trees. Trees are generally planted and left to grow on their own.
Nevertheless, some respondents (35%) reported to have carried out
some kind of weeding in their woodlots or for agroforestry trees. This
percentage is yet still inadequate since weeding is considered as one of
the most important post-planting carethat can lead healthy woodlots
and forestplantations with increased tree vigour and survival rate.
Meanwhile, it was revealed that trees on private land survived better
than those planted on public lands. Indeed, the mean survival rate of
51% in agroforestry on private land between 2007 and 2011was low
but higher than the mean survival rate of 30% found in agroforestry on
public land. In woodlots and forest plantations, private trees survived
at 65% while on public land trees survived at 40% on average from
2007 to 2011.
Basing on above findings, it should be recommended that tree planting
and tending activities during community works (Umugandarusange)
should be supervised by skilled workers, instead of leaving people on
their own without proper instructions on proper tree planting and
tending techniques. Local authorities should also organize regular and
supervised community works on each site where public trees have
been planted in order to ensure proper post-planting care which will
likely improve survival rate of planted trees. Furthermore, the forest
extension services should be strengthened in order to ensure adequate
farmer education and follow up of planted trees and forests.This study
should also be carried out in other parts of the country in order to find
out whether or not the underlying factors behind low survival rate after
each tree planting season in Huye District are similar to those in other
Districts.
Rwanda Journal, Series E: Agricultural Sciences Vol. 1 No. 1, 2013 61
References
1. Evans, J., and Turnbull, J. (2004).Plantation forestry in the
Tropics.Forest Nurseries.Oxford University Press. Oxford
2. Elefritz, M., Atkinson, M.M., and Fitzgerald, S.A. (1998).
Common mistakes while tree planting. Tree planting techniques,
p.8. Oregon
3. Foster, R. S. and Blaine, J. (1978). Urban tree survival: trees in the
sidewalk. Journal of Arboriculture 4(1): 14-17.
4. Huye District EDPRS Self-Assessment (HDESA), (2011).EDPRS
Self-Assessment Report, HuyeDistict, Huye.
5. Landis, T.D., and Haase, S. (2008). Maintenance of stocks
“Quality after they are harvested”.Forest Nursery Notes 28(14),
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6. Maginnis, S. and Jackson, W. (2003). The role of planted forests in
forest landscape restoration.
7. Nduwamungu, J. (2011). Forest plantations and woodlots in
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