Paet IV.] Caccia ; Selection method of treatment in India. 327 
Assuming that one-third of the pyinkado and kanyin and two-thirds of all 
the other species will be removed during the ‘20 years’ felling rotation, the 
average annual yield will be : — 
Teak .... 
3,004 
or 
Pyinkado .... 
5,708 
i 1 
Pyinma .... 
. 15,.507 
if 
Kanyin .... 
7,4‘23 
> f 
Eng .... 
. 17,044 
i> 
All others .... 
. 175,135 
if 
120 
95 
517 
124 
588 
5,808 
This is a very rough estimate, but no accurate data arc yet obtainable to 
calculate how long it takes the various species to jjass from Class II into Class I. 
The annual yield will be larger towards tbe end of the felling rotation as a 
proportion of trees under 0 feet in girth will, by that time, have reached the 
prescribed girth and become mature. 
The fellings are only prescribed for 20 years at the end of which time it will 
be necessary to revise and jjrobably alter the plan. 
In other cases, the felling rotation may with considerable ad- 
vantage be made equal to the number of 
Example .3. Foiling rotation years required for the second class tree 
=nuinber of years passed in , , ■ i , i 
rs^nultimate girth clU. commercial maturity, as has 
been done in the working plan for the 
Samta forests of the Siiighbhum Division, Dengal.* 
These forests should obviously be worked with a view to obtaining large 
timber for sleepers, boat construction, houses, etc. 
In view of the facts that we are not quite sure of the rate of growth (the 
data being insufficient), that w’e have no figures of the total number of trees in 
the several classes, and that much of the hill sal is unfit for working, it has 
been decided to limit the fellings by area, especially by the area of the Valley 
type, which is the only part of the crop likely to yield important quantities of 
marketable timber, and to remove from each coupe all trees over 0 feet in girth. 
From what has been stated regarding the rate of growth, it appears that 
in Valley type areas most of the sal trees which arc at present 5 feet to 0 feet 
in girth will become over 0 feet in girth in .‘JO years; and from the valuation 
surveys and from general observation it is clear that the number of trees wliich 
are now 5 feet to 0 feet in girth exceeds the number of trees which are now 
over 0 feet, and that trees between 4 feet and 5 feet are more numerous than 
those between 5 feet and 0 feet girtli. Hence it appears quite safe to adopt a 
felling rotation of .‘JO years removing all trees over 0 feet in girth from each 
coupe as it is worked. 
The difficult nature of the country, making it impracticable to mark over 
very large areas annually, taken with the existing defective state of the com- 
munications, renders it impossible to work over the whole area of tlie forests in 
a period much less than .‘JO years, and .30 years is hence adopted as the length of 
the felling rotation. 
The period for which fellings are prescribed is however half of the felling 
rotation, i.e., 15 years. 
It is intended that a rev j^n of the plan shall b e undertaken after 1.5 years. 
* Working Plan for the reserved forests of the Singhbhum Division. Bcnrral 
by H. H. Haines, I.F.S., 1906. ’ ' ^ ’ 
