THE NAVAL STORES INDUSTRY. 
49 
EFFECT OF VARYING FREQUENCY OF CHIPPING ON YIELD— CALIFORNIA. 
Table 20 shows the yields obtained from three similar sets of 50 
faces, each chipped at 3, 5, and 7 day intervals for the same period. 
Table 20. — Yields obtained by chipping at different intervals — California (50 faces in 
each set). 
3-day intervals. 
5-day intervals. 
7-day intervals. 
Date of 
chipping. 
Weight 
of dip. 
Date of 
chipping. 
Weight 
of dip. 
Date of 
chipping. 
Weight 
of dip. 
1912. 
June 11 
June 23 
July 5 
July 17 
July 29 
Aug. 10 
Total . . 
Pounds. 
46 
49 
66 
69 
81 
81 
1912. 
June 14 . . . 
June 29... 
July 14.... 
July 29. . . . 
Aug. 8.... 
Pounds. 
35J 
47 
49£ 
57 
45 
1912. 
June 13.. . 
June 27.. . 
July 11.... 
July 25. . . . 
Aug. 8 
Pounds. 
25 
31 
31 
40 
45| 
392 
234 
172J 
Over twice as much gum was obtained by chipping at 3-day inter- 
vals as at 7-day intervals. 
SUGGESTIONS FOR SPECIFICATIONS. 
HANGING CUPS 
1. The distance from the ground to the apex of the first streak 
shall not exceed 10 inches. 
2. No " blazes" or similar scarification of the tree shall extend 
below the gutter or apron. The surface prepared for the placement 
of the gutters or aprons shall not extend beyond the ends of the same. 
3. The peak of the first streak shall not be more than 2 inches 
above the gutter or apron. 
4. The " streak" or gash made for the placement of the gutters or 
aprons shall not penetrate the wood of the tree more than one-half 
inch, the measurement to be taken from the dividing line between 
the wood and bark. 
5. The gutters or aprons must be so attached that no "gum" flows 
between the tree and the gutters or aprons, or flows over the edge of 
same so as to fall without the cup or other receptacle. 
6. For the first three years the cups and gutters shall be raised 
each spring to the top of the face worked the previous season. 
7. A bar or strip of live bark not less than 4 inches wide in the 
narrowest place shall be left between the faces. 
CHIPPING. 
1. No tree under 10 inches in diameter shall be tapped. Minimum 
diameter of tree to carry one face, 10 inches; minimum diameter of 
tree to carry two faces, 16 inches; no tree shall carry more than two 
faces. 
