126 
Indian Forest Records. 
[VoL. I. 
PART II. 
THE DEVELOPMENT OF THE STEM OF SINGLE SAL 
TREES. 
Section 1 — Preliminary Matters. 
A Sal tree consists of a crown, stem, and roots. The stem is from 
an economic point of view by far the most valuable and important part 
of the tree, and the study of the progress of its growth is of the greatest 
importance to the forester. In the case of trees possessing distinct 
annual rings, the development of the stem, its growth in height, dia- 
meter and volume, the determination of the form factor, and the rate 
per cent, of volume increment at different periods of the tree’s life may 
be accurately and easily ascertained by means of a “Stem analysis”. 
Unfortunately this is not usually possible in the case of the Sal ; and the 
forester has to resort to the periodical measurement of selected trees in 
sample plots. On this account the collection of accurate statistical 
data becomes a laborious operation, requiring sustained attention — a 
fact w’hich may to some extent explain the meagreness of the informa- 
tion at present available ; the almost complete absence of Sal trees of 
known age adding to the difficulties experienced. It must be remem- 
bered, moreover, that statistics based on insufficient measurements are 
worthless for all practical purposes ; the value of any table or figure 
being proportionate to the number of trees measured. 
Section 2. — Height Increment. 
Laws which (jovern height growth of single trees in general : — 
A. — Seedlings— 
I. Height growth is very slow at firet, and up to a certain age (fifth year or 
later). 
II. After that age, height increment increases rapidly, and usually culminates 
on the tree attaining an age of 10 to 50 years (age not known for Sal). 
III. After culmination height increment drops until it reaches a low level at 
which it remains constant. 
lA. Height growth is directly proi)ortional to soil and cUmate. 
V. Trees grown in properly thinned woods develop greater height than those 
grown isolated or in over-crowded woods. 
