7 
Part ill.] E. Benskin and A. Rodger : Note on Thitsi. 
which left 4 days for rest. They only work in those parts of the forest 
where the tree is abundant and trees fit to tap stand closer together. 
‘ ‘ The tree yields nothing while it is leafless in the hot season, and the 
best season for working is from July to October. One man collects 
40-50 viss (146 to 182 lbs.) in one season ; at Tyemyouk the viss sells 
for 12 annas, and at Rangoon for one rupee.” 
The thitsi tree is closely allied to the Japanese lacquer tree Rhus 
vernicifera, and it may be of interest to note here that the Japanese 
consider that the sap obtained from the lower part of the tree is superior 
to that obtained from the higher parts of the trunk. 
The varnish exudes from the tree as a thick greyish fluid which turns 
brown, and then jet black on exposure to air. Great care should be taken 
in handling the substance as it is liable to cause inflammatory swellings 
on the exposed parts of the body. It is said that some people will not 
cut or tap the tree on this account, while on others it has no effect. This 
poisonous property is stated to be due to a volatile oil, against which 
an infusion of teak wood is recommended. The writer (E. Benskin) in 
experimenting with this substance at the Forest Research Institute 
at Dehra Dun suffered considerably from those swellings but found 
that the varnish, when adulterated with ferric oxide up to 10 per cent, 
of its weight, has apparently no effect on the skin, and the addition 
of this mineral considerably increases the drying capacity of the 
varnish. Mr. Puran Singh suggests that, to get rid of this poisonous 
substance, the oleo-resin should be stirred in the open in shallow vessels. 
Most writers testify to the wanton damage that is being done to 
the trees by over-tapping. Steps should therefore be taken to regulate 
the tapping, as unless this is done, a sustained annual yield may become 
impossible in the near future. Such regulations should limit the mini¬ 
mum size of the trees to be tapped, the number of blazes that should be 
made on trees of different girth, and trees which have been tapped 
should be allowed to rest for a number of years in order to recover 
from any damage resulting from tapping. Forest officers in Burma, 
however, are not all agreed as to the minimum size that should be 
tapped, and it would be useful if experiments were made to determine 
the girth at which trees can be tapped without seriously interfering 
with their growth and productivity. 
6. Uses of the Oleo-resin. 
Although the timber of Melanorrhcea usitata is not at present used 
to any great extent, the tree is highly prized by the Burmese on account 
of the oleo-resin or so-called varnish which exudes from the trunk when 
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