THE HEVEA RUBBER TREE IN THE AMAZON VALLEY 19 
At the present day the seringueiro makes no special effort to avoid 
cutting into the cambium. At every stroke of the ax he not only cuts 
into the cambium but into the wood from 3 to 12 millimeters. Fre- 
quently a piece of wood and bark half the size of a man's hand is 
broken out, and at least a small chip nearly always results from 
the cut. Probably the South American methods were once better; 
certainly the methods in the East were formerly worse; but by 
comparison with the tapping done in the oriental plantations to-day 
that in Brazil is incredibly stupid and barbarous. 
In the Acre Territory of Brazil and in the adjoining Northwest 
Territory of Bolivia the treatment accorded the trees seems a little 
less vicious than in the region of the Madeira and its tributaries. 
The machadinhos used here have a cutting edge 5 centimeters long, 
which, however, is capable of chopping out a chip 7 to 7.5 centi- 
meters long, 5 to 6 centimeters wide, and 0.5 centimeter thick as an 
average. 
Apparently the number of cuts to the tree is less where the larger 
machadinho is used. On the estrada from which the data in Table 1 
were taken the average number of cuts per tree is 2.3 where the 
trees average 114 centimeters in circumference. On an estrada in 
Bolivia, between Cobija and Porvenir, the number of cuts was also 
2.3 per tree, but the trees here averaged 162 centimeters in circum- 
ference. 
A second estrada in Bolivia, data from which are given in Table 2, 
has the much higher average of 3.1 cuts per tree on trees 166.7 centi- 
meters in circumference. But on closer examination it proves that 
the trees in Matto Grosso have one cut for every 49 centimeters of 
circumference; the estradas from the Bolivian Acre district have one 
Gut for each 70.5 centimeters of circumference and one for each 53.6 
centimeters of circumference, respectively, so the latter are much 
less severely tapped than the former. 
The number of cuts is proportional to the size of the tree, though 
deviations from the proportion frequently occur. A high yield from 
a given tree is likely to cause the seringueiro to increase the number 
of cuts, while a low yield will lead to a smaller number of cuts than 
a large tree would normally receive. Such tendencies may be noted 
in Table 2 in trees Nos. 24, 27, 29, and 42. 
One can only guess what the number of cuts per tree used to be 
; in the days of high-priced rubber, but they were at least what one 
would call numerous. Walle (44-) shows a photograph of a rubber 
tree which bears 19 cups on the area exposed to the camera. The 
machadinhos in those clays were smaller than those generally used 
now, but even so the tapping was excessive. 
The consumption of bark is always great with machadinho tap- 
ping. The vertical distance between cuts is generally about 10 cen- 
timeters, of which 5 or 6 centimeters represents the bark broken out 
by the stroke of the ax and the remaining 4 or 5 centimeters the 
bark left intact. Each estrada is tapped approximately twice a 
week over a period of six months or more. Tapping for 30 weeks 
would exhaust 6 meters of tapping space. Three meters is as high 
as a tapper can reach, and this usually represents the maximum 
height of tapping. Most seringals now prohibit the use of ladders 
