380 
Indian Forest Records. 
[VOL. I. 
Taking these as given, the following are calculated from them : — 
60 per cent. Class III become I. 
36 per cent. Class IV become I. 
12 per cent. Class V become I. 
45 per cent. Class IV become II. 
20 per cent. Class V become III. 
15 per cent. Class V become II. 
The following statement gives the stock of firs calculated for 1900 ; — 
Species. 
1 
II 
III 
IV 
V 
Firs 
31,198 
33,837 
63,225 
1,18,630 
? - 
Taking the percentages given above, the annual possibility is calculated for 
the whole rotation of 120 years, the excess trees in Class I being distributed 
throughout the rotation, the average annual yield being — 
( 31198 X + (33837 x f hs) _+ (‘'’3225 x + (118630 X 
(120 X %°)* 
^ 29698 + 2707C + 37935 + 4270 
140 
= 981 trees. 
Taking the average annual yield of firs for the whole rotation of 120 years 
at 981 trees per annum, there ought to be 981 x x =20,123 trees now 
in Class I, but there are 31,198 or an excess of 11,075. 
And the following statement shows the number actually prescribed to be 
exploited annually : — 
Specie.®. 
A. A. Y. for 
the whole rotation. 
Nnmbei' of 
trees. 
Excess or de6cit 
stack in exploit- 
able class. 
Annual fellings 
prescribed. 
Firs 
981 
11,075 
800 
Lastly ill exceptional cases it may happen at the commencement 
of the first period of systematic working 
Example 4. SurjOus stock at that the surplus stock wliich should be 
commencement is inadequate. , t Ti i • • ro • . 
standing on the ground is insumcient or 
wanting. The procedure then to be followed may either be that of 
* As the felling cycle is 40 years, there should always be on the ground x 
(average annual yield) Class 1 trees; therefore must be added to the rotation 
for the denominator. 
