OLEORESIN PRODUCTION 33 
fig. 6) is so narrow that it is done in the lightwood. The current 
prejudice against chipping in the lightwood probably arises from the 
fact that at times the lightwood (PL III, fig. 1), especially when it 
is most conspicuous, may indicate the beginning of dry-facing. 
Under such conditions the decreased production occurring may be 
revived to a certain extent by chipping ahead of this lightwood up 
the tree for several inches, until a region which is less dried out and 
injured is reached. It is therefore only when it indicates the satu- 
rated condition of dead and dried cells, especially the devitalized 
condition of the resiniferous parenchyma, that the presence of light- 
wood should be considered detrimental. Such a condition, more- 
over, is much more likely to occur in high chipping which is designed 
to keep ahead of the lightwood than in narrow chipping (one-half 
inch or less) which is done in the region of the lightwood. 
SUGGESTIONS FOR FUTURE PRACTICE. 
Many of the statements made in the following discussion are not 
based upon the results from definite experiments, but are derived 
from the writer's observations made on successful commercial opera- 
tions or from the statements of experienced operators, or are deduc- 
tions from the data presented in the preceding pages. They are, 
therefore, to be considered as suggestions only and are advanced 
tentatively, subject to further investigation, because in the light of 
our present knowledge they appear to be beneficial in character. 
SIZE OF THE TIMBER. 
From the preceding discussion, especially that with reference to 
light cupping (pp. 29 to 31), it is apparent that it is unprofitable to 
turpentine very small timber. An excellent example of conservative 
operation, from the standpoint of present practice in the United 
States, is the method specified in the Florida National Forest tur- 
pentine leases (page 25). 
LOCATION AND SIZE OF THE FACES. 
One of the most obvious sources of waste in turpentine operations, 
and apparently a matter which has received relatively little compe- 
tent attention, is the matter of placing the faces on the trees. Bad 
practice of this sort, due to carelessness, is only too commonly found. 
Figures 2 and 3 of Plate VII, illustrating such bad methods, are in 
sharp contrast with figure 1 of Plate VII, which illustrates the proper 
placing of faces. This practice of leaving insufficient bark between 
faces is a fundamental error of the worst sort, since it means waste 
throughout the operation. Six-inch, or at least 4-inch bark bars 
should be left between faces, and the width of face should be in pro- 
