106 



ent jungle conditions and type of labor, since supervision in the more 

 or less inaccessible regions is almost impossible and would entail 

 considerable expense. As a result no particular premium is placed on 

 caution and care in tapping, and the only prerequisites of a chiclero 

 under the present system are the ability to climb with the aid of a 

 rope and make incisions which will secure the maximum yield of 

 latex and convey it without loss to the collecting bag at the base of 

 the tree. In their eagerness to secure the maximum amount of chicle 

 during the rain}- season, chicleros often overtap the trees and cause 

 serious injury. Little regard is paid by the inexperienced chiclero to 

 depth of tapping and injury to the cambium. According to conser^-a- 

 tive chicle contractors, approximately fifteen per cent of the tapped 

 trees are eventually killed by the present native machete spiral 

 method of tapping. Hoar (1924) claims that twenty-five per cent are 

 killed. This estimate is based primarily on the number of dead trees 

 which may be seen in the chicle areas and does not, however, rep- 

 resent accurate annual counts and careful observation. To the casual 

 and inexperienced observer it would appear at first sight that the 

 number killed each year is appallingly high, since the chicle forests 

 contain a high number of dead standing trees, many of which bear 

 the tapping scars. This large number, however, represents the ac- 

 cumulation of many years, since the sapodilla tree, because of its 

 hardness, usually remains standing for several years after death and 

 decays very slowly. Furthermore, many trees die a natural death or 

 are killed by wood borers which enter after tapping. Consequently, 

 the number of dead trees in any particular chicle area is not an ac- 

 curate index of the number that is killed by tapping each year. 



Nevertheless, the long machete used in the native system of 

 bleeding is a difficult tool to control wnth respect to depth of tapping, 

 and the cambium is often completely severed at the point of tangency 

 of the bole and the cut. Quite frequently the cambium is removed 

 with the chip of bark, and the wood is accordingly laid bare. Direct 

 exposure thus of the cambium and xylem to the tropical midday 

 heat often leads to a rapid drying out of the uninjured cambium and 

 cortex immediately adjacent to the exposed region. This drying out 

 may extend as much as an inch or more under the bark all around 

 the injury, forming a dead region many times as large as the original 

 exposed area. This is well illustrated by the trees shown in Figures 

 9 and 10. Immediately after tapping in October, 1927, the cuts on 



