THE THEORY AND PRACTICE OF WORKING PLANS 143 



crops * — e.g., by shallow and light chipping the first faces can 

 be chipped for three years, when the faces will be about 45 to 

 50 inches in height, the cups being moved up each year. Then 

 the faces are worked with a " puller," a chipping tool with a 

 long handle, for another three years, which makes the faces 

 from 7 to 8 feet high. The tree is then allowed to recuperate 

 for three years, when " back cups " are placed between the old 

 faces and worked for three years. The final period of three 

 years' working is secured from the high-face back cups. Thus 

 each tree is worked for twelve years, extending over a period of 

 fifteen. When the trees have been completely worked, they are 

 cut for saw-timber, ties, or other material. f Certain of them 

 are left as seed trees if that form of reproduction is sought, 

 or else the seeding is from the side by the clearcutting strip 

 method. In case of artificial reproduction, the worked and 

 logged area is seeded or planted. When the young growth 

 has reached sufficient size, the larger trees are turpentined, 

 and thus the cycle is completed. | 



* A " crop " is commonly considered as containing 10,000 cups. 



t The turpentined trees of France are highly prized in England as mine tim- 

 bers. 



X For further details, see " The Administration of a National Forest for Naval 

 Stores," I. F. Eldredge, Proc. Soc. Am. Foresters, Vol. IX, No. 3, pp. 310-326. 



