TM 5-6675-322-2
(b) Observer stands at sampling point and aims instrument at diameter
o f a l l v i s i b l e t r e e s a t b r e a s t h e i g h t ( D B H ).
( I f a t r e e i s p a r t i a l l y o b s c u r e d,
observer should shift position, remaining at same distance from tree, to take
reading on tree, and then move back to his original position. )
( c ) P u s h r e l e a s e b u t t o n t o p e r m i t s c a l e t o s h i f t .
(d) All trees that have a diameter wider than scale 2 are counted.
Trees that have an equal diameter to scale 2 are not counted. Trees that have a
diameter smaller than scale 2 are not counted.
(e) The number of trees counted are multiplied by the scale number
( c o u n t i n g f a c t o r ).
Example: Scale 2 - 32 trees counted.
2 X 3 2 = 6 4
(f) The number of sampling points chosen is determined by area of tree
stand, uniformity of tree stand and accuracy required.
If scale 4 is chosen for readings:
Area smaller than 4 hectares
Use 4 sampling points per hectare
Area 4-8 hectares
Use 3.8 sampling points per hectare
Area 8-16 hectares
Use 3.5 sampling points per hectare
Area 16-32 hectares
Use 3.1 sampling points per hectare
Area 32-64 hectares
Use 2.6 sampling points per hectare
Area greater than 64 hectares
Use 2 sampling points per hectare
If scale 2 is chosen, multiply above points by 0.6 to determine number of
sampling points required.
If scale 1 is chosen, multiply above points by 0.4 to determine number of
sampling points required.
NOTE
Choose sampling points at random.
Do not choose convenient sampling
p o i n t s f o r a c c e s s i b i l i t y , o r s a m p l i n g w i l l b e i n e r r o r .
(g) Average values taken at each sampling point to determine basal
area.
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