Part IV.] Caccia : Selection method of treatment in India. 338 
It is also evident that when the possibility under the Oudh 
Method is taken to be equal to the whole of the Class I trees flus | 
the Class II trees, that the yield so calculated will be identical with 
that which would be obtained by the Burma Method, when the possi- 
bility is calculated for a period equal to the number of years taken 
for a tree of the lowest dimensions of Class II to attain the lowest 
exploitable dimensions. 
Furthermore under Brandis’ Method when the felling rotation 
is a long one, the maximum age of the trees may be so raised as to 
cause serious deterioration by the time their turn comes to be har- 
vested. 
i. — Brandis' Method. 
In Brandis’ Method the possibility is based on the number of 
exploitable or Class I trees existing in the forest ; it being permis- 
sible to remove the whole of these in the time which it takes to 
replace them. In calculating the possibility it will be necessary 
then to ascertain — 
(i) the number of first class trees in the forest ; and 
(ii) the number of years it takes to replace them. 
By dividing the former figure by the latter, the maximum num- 
ber of trees which it may be possible (subject to sylvicultural con- 
siderations) to cut annually is determined. 
Thus, suppose the rotation be fixed at 100 years, which under the 
selection system is represented by a tree 6 feet in girth (the minimum 
exploitable girth). And suppose the enumeration of the forest has 
been carried out in 6-inch girth classes, and that it has been ascer- 
tained that each girth class represents a period of 15 years. Then, 
in the normally constituted forest, at the commencement of the fell- 
ing rotation of 15 years, the age of trees in the Class I would vary 
between 101 and 115, and that of the trees in girth Class II between 
86 — 100 and so on. The trees in Class I present at the commence- 
ment of operations are exploited during the period of 15 years; it 
follows that in the first year trees 101 — 115 will be obtained, in the 
second year trees between 102 — 116, etc., etc., and in the last year 
the age of the trees will be 116 — 130, which gives an average age of 
115 vears. 
