Jan. 1,1925 Effect of Height of Chipping on Oleoresin Production 
83 
obtained from the area. The test 
probably will be continued until 1927. 
Similar tests will be conducted by Dr. 
Cary and the writer in cooperation 
with other interested operators. Vari¬ 
ous types of slash and longleaf pine 
timber in widely scattered localities in 
the South are to be studied. Practi¬ 
cally stated, the object of this investi¬ 
gation, of which the test described 
below is a part, is to determine whether 
there is any good reason why operators 
should not cut “lower” faces; that is, 
remove at each cutting less wood than 
is now customary. 
DESCRIPTION OF THE TEST 
CHARACTER OF TREES SELECTED 
The 60 longleaf pine test trees con¬ 
stituting three matched groups are lo¬ 
cated near a main road in the Florida 
National Forest and are easily accessi¬ 
ble from the Ranger Station at Camp 
Pinchot, Valparaiso, Fla. The tract in 
which they stand had been set aside to 
be worked commercially for turpentine, 
beginning in 1923. Conditions of soil 
and general site apparently are com¬ 
parable for all. The individual trees 
were matched by diameter measure¬ 
ment breast high and by visual inspec¬ 
tion for similar external features, such 
as crown density, character of bark, and 
absence of wounds or fire scars. 
It is realized that 60 trees is a small 
number. The results and conclusions 
drawn are, consequently, to be con¬ 
sidered as indicative only. The help¬ 
fulness of these small tests, however, 
has been clearly demonstrated. They 
offer opportunities for careful detailed 
selection and matching of individual 
trees which larger ones do not, so that 
they may be compared as closely as 
possible. This was true in the test de¬ 
scribed, where both external features 
and internal structure run parallel to a 
fairly satisfactory degree in the groups. 
The test trees were divided into three 
similar plots or groups of 20 each, to be 
chipped at different heights. They 
were distinguished by suitable mark¬ 
ings, that is, one spot of white paint on 
the bark of each tree in Group 1 
and two and three spots, respectively, 
for each tree of Groups 2 and 3. The 
average diameter breast high for the 
three groups was practically the same 
(11.5 inches), with individual variations 
ranging between 9 and 14 inches. The 
number of annual rings in the half inch 
of wood next the bark, counted on chips 
removed during the turpentining, 
showed group averages of 15.6, 14.6, 
and 18 rings, respectively. Groups 
1 and 2 were selected on November 24, 
1922. The third group, representing 
the commercial practice of many op¬ 
erators, was added for observation on 
April 9, 1923. 
A view showing some of the Group 1 
trees which are generally typical for the 
stand in the test is shown in Plate 3. 
The timber is not young second-growth. 
It is generally uniform in character, 
typical of much that is now being 
worked, but is not to be classed with 
fast-growing young longleaf pine on 
better soil. Neither is it like some of 
the old, over-mature trees which may 
be found in this locality. It presents a 
healthy external appearance and a 
normal wood formation, as is indicated 
by the number of rings per inch, shown 
in the accompanying photomicrographs 
(PI. 2). 
METHODS OF CHIPPING 
History of first year’s work.— 
The usual advance streak was cut on all 
trees three or four weeks before the 
regular chipping, which began on 
February 17, 1923. 
Because of the Deputy Supervisor’s 
illness, the first six streaks were cut 
without special supervisioh, }/% inch 
high, according to the standard prac¬ 
tice of the Forest Service, and com¬ 
parative test chipping was not regu¬ 
larly begun until April 9. Conse¬ 
quently, on that date the faces were an 
inch and a half higher than was in¬ 
tended for Group 1 and lower by the 
same distance for Group 3. It chanced, 
moreover, in surveying the commercial 
crop 6 lines through the tract that the 
trees situated in Group 2 were included 
in a separate crop from the other test 
trees, so that at first they were chipped 
by a different workman and later in 
the week. This would tend to make 
the yield at the first dipping appear 
unduly low for Group 2. After June 1 
it was arranged that all trees should be 
chipped on the same day by the same 
man. Collection of gum (dipping) 
occurred at the intervals noted in 
Table I. 
The faces are all placed low on the 
trees, as is the regular practice on the 
Forest, with the first streak 7 inches or 
less from the ground. Regular chip¬ 
ping for the year stopped about No¬ 
vember 8, 1923, at 32 streaks, but a 
thirty-third streak was cut to obtain 
material for microscopic study. At 
the end of the season the faces were 
scraped. The yields of gum and 
6 A "crop” is approximately 10,000 faces, or about the number that one man will chip in a week. 
