COMMUNITY TREE PLANTING GUIDELINE - SPGS

LAWLOG PRODUCTION GRANT SCHEME
5.3 Thinning
This is an operation deliberately carried out at different
stages of tree growth by selecting and removing some
of the living trees from a given plantation stand before
the final clear cutting.
5.3.1 Why should I thin my
trees?
As trees grow, they start competing with one another
for light, nutrients, water and space thereby making
them grow abnormally. Therefore, some of the trees
in the plantation life span should be systematically
removed (whether good or not) in order to reduce
the competition between the trees. This allows the
best remaining trees to grow faster and larger, thus
increasing the value of your plantation.
5.3.2 When should thinning
be done?
5.3 Thinning
This is an operation deliberately carried out at different stages of tree growth by selecting
and removing some of the living trees from a given plantation stand before the final clear
cutting.
Generally 5.3.1 Why should it depends I thin my on trees? tree species, its growth rate and
extent of maintenance. Thus like pruning, there is no
compulsory time for thinning plantations but it should
be done before competition (crowns and branches start
trees grow faster and larger, thus increasing the value of your plantation.
touching) begins. It is advisable to do first thinning
only 5.3.2 after When first should pruning thinning be for done? clear view of trees and safe
passage. The rest of the thinning operations can be
done before pruning to save money from pruning trees
that are after all going to be thinned out.
As trees grow, they start competing with one another for light, nutrients, water
and space thereby making them grow abnormally. Therefore, some of the trees in
the plantation life span should be systematically removed (whether good or not) in
order to reduce the competition between the trees. This allows the best remaining
Generally it depends on tree species, its growth rate and extent of maintenance.
Thus like pruning, there is no compulsory time for thinning plantations but it
should be done before competition (crowns and branches start touching) begins.
It is advisable to do first thinning only after first pruning for clear view of trees
and safe passage. The rest of the thinning operations can be done before pruning
to save money from pruning trees that are after all going to be thinned out.
Table 7 below shows the suggested thinning type, age
and for a pine number plantation. of stems left for a pine plantation.
Table 7 below shows the suggested thinning type, age and number of stems left
Thinning type Age (years) Stems left
1 st 5 to 7 750
2 nd 7 to 10 500
3 rd 10 to 14 250 to 350
This means at any tree spacing used, e.g. 3mx3m where
there are 1,111 trees/ha, the number of trees to be
removed per ha at first thinning would be (1,111-750)
years.
361. In the 2nd thinning it would be (750-500) 250 and
at 5.3.3 3rd What thinning are the steps you taken remove during (500-350) a thinning operation? 150 to leave you
with described 350 below: trees per ha for final clear cutting at 18-25
years. Each thining operation requires that you follow
1) What is the appropriate thinning plot size?
some important steps for success.
This means at any tree spacing used, e.g. 3mx3m where there are 1,111 trees/ha,
the number of trees to be removed per ha at first thinning would be (1,111-750)
361. In the 2 nd thinning it would be (750-500) 250 and at 3 rd thinning you remove
(500-350) 150 to leave you with 350 trees per ha for final clear cutting at 18-25
In order to successfully carry out thinning of your trees, please follow steps (1-5)
This depends on the spacing of trees. For example the thinning plot could be one
of 5 trees by 5 or 10 trees by 10 trees. For 5 trees by 5 trees area it gives a
thinning plot size of 15m x 15m (225m 2 ) when your spacing is 3m x 3m.
5.3.3 2) How many What of these plots are (225m 2) the are in one steps hectare? taken
As one hectare is 10,000m
during a 2 , this gives (10,000m
thinning 2 ÷ 225m
operation?
2 ) 44 plots.
3) How many trees do I need to leave on each hectare after first thinning?
An example of a well thinned stand like this will allow trees to
quickly gain more volume
This 2-year old plantation of E. grandis is for fuelwood (James Finlay
Ltd.) and thus has many trees per hectare (i.e. high stocking): if
grown for sawlogs, it would have to be thinned to give the best trees
more growing space.
In order to successfully carry out thinning of your trees,
please follow steps (1-5) described below:
1) What is the appropriate thinning plot size?
This depends on the spacing of trees. For example
the thinning plot could be one of 5 trees by 5 or 10
trees by 10 trees. For 5 trees by 5 trees area it gives
a thinning plot size of 15m x 15m (225m 2 ) when
your spacing is 3m x 3m.
2) How many of these plots (225m 2 ) are in one
hectare?
As one hectare is 10,000m 2 , this gives (10,000m 2 ÷
225m 2 ) 44 plots.
3) How many trees do I need to leave on each hectare
after first thinning?
For our example of table 7 above, it is 750 stems
per hectare
4) How many trees should I leave on each plot after
thinning?
Number of trees to be left on each plot = 750 ÷
44=17trees
5) Therefore, how many trees should I thin out
(remove) from each thinning plot?
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Community Tree Planting Guideline
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