OLEORESIST PRODUCTION. 
It is customary to cut from 28 to 40 streaks each season. Often 
one-third of the trees in a commercial operation die, chiefly because 
of the undue severity of the methods used in turpentining. In some 
places the old method of cutting boxes or cavities at the butts of 
the trees (PI. I, fig. 1) to hold the exuding gum, is still used, al- 
though, for the most part, cups of various types are employed (PI. 
I, figs. 1, 3, 5, and 6). 
After chipping, the gum or oleoresin exudes from the freshly cut 
surface. The most abundant exudation (88 per cent) has been 
observed to occur during the first three days after chipping. 
(Table 1.) 
Table 1. — Rate of exudation of gum from chipped longleaf pine. 1 
Day. 
Grams of 
gum. 
Total 
exudation, 
per cent. 
First 
113.0 
22.5 
13.5 
9.0 
9.0 
1.0 
67.26 
Second 
13.39 
Third 
8.04 
Fourth 
5.36 
Fifth and sixth 
5.36 
.59 
Total 
168.0 
(=0.37 lb.) 
100 00 
i For. Serv. Bui. 90, p. 6. 
SIGNIFICANCE OF RESIN PASSAGES PRESENT IN THE UNTURPENTINED TREES. 
The gum which exudes during the first weeks of a virgin or first- 
year operation comes from the normal resin passages which were al- 
ready present in the round or unturpentined timber. Plate II, figure 
1, shows the characteristic condition of the trees at Columbia, Miss., 
on April 13, 1916. At that time no new wood or resiniferous tissue 
for the 1916 ring had formed. Plate II, figure 2, shows a cross sec- 
tion cut from a tree on June 13, 1916. The development of new wood 
cells is apparent, and new resiniferous tissue may be seen to be dif- 
ferentiating in the region next the cambium. Plate II, figure 3, shows 
a cross section cut from a tree on July 5, 1916. Marked differences 
between individual trees occurred, however, and the range of develop- 
ment of the 1916 ring shown in the three figures might be encoun- 
tered in material cut at the same time from different trees during 
either late May or early June. Often it is the end of May before the 
new and augmented development of the resiniferous tissue, formed 
after wounding in the new wood, is sufficiently advanced to yield 
appreciable amounts of resin. Indeed it frequently happens that in 
a virgin operation the normal resin passages present in the round 
timber may fill the cups not only for the first but also for the second 
and sometimes for the third time, or " dipping," before any new resin 
