RUBBER PLANTING 147 



is found to flow from the lowest cut; and some of the 

 upper cuts may even cease altogether to yield latex, 

 whilst there is still an inch or more of bark remaining 

 untapped. It is probably best in all cases to leave the 

 last inch or so of bark untapped, and to continue tapping 

 the lowest cut only, if the time has not arrived for 

 passing on to a fresh area of bark. When the same 

 section of the tree comes to be tapped a second time, it 

 may be marked out an inch higher than before, in order 

 that the unused slips of bark may now be tapped first. 



In an experiment at Henaratgoda 29 old trees were 

 tapped daily on six wide NTs, spaced at vertical intervals 

 of a foot. During the first month's tapping the three 

 upper cuts yielded together a daily average of 558 c.c. 

 of latex (nearly a pint), and the three lower cuts a daily 

 average of 561 c.c. The quantities were therefore almost 

 exactly equal, although the latex from the lower cuts 

 contained a slightly higher proportion of rubber. 

 During the six months' tapping, at the end of which 

 the bark between the cuts had been almost entirely 

 removed, the average daily yield from each of the six 

 cuts was as follows: 



TABLE XXVIII 



Cut 12345 6 



Yield c.c. ... 77 86 98 82 83 400 



Thus, when the bark between the cuts was nearly 

 exhausted, the lowest cut was yielding as much latex as 

 all the other five put together. In addition, the latex 



TO 2 



