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PLATE VII

FIG. 1.-Well-placed faces. This insures the fullest return from the tree for the labor of operation.
FIG. 2.-Bad placing of faces at the beginning of the operation. This means waste and loss at every stage.
FIG. 3.-The effects at a later stage of placing faces too close together. Note dead and dry face.
FIG. 4.-The beginning of the third year of turpentining, May, 1917, in a conservatively chipped tree.
About 16 inches height of chipping surface was cut annually. Standard Practice Florida National

Forest.

FIG. 5.-The beginning of the sixth year of turpentining, June 6, 1917, on a well managed commercial operation. In its fifth year about 45 barrels of turpentine were said to have been made from this crop. FIG. 6.-One tree from the area shown in figure 8. This was the beginning (June 6, 1917) of the second year of this operation. Note chipping -inch to 1 inch deep. The sapwood in this case was about 3 inches wide. Thirty-three streaks were cut each year.

FIG. 7.-Excellent opportunities for future turpentining are offered by the good reproduction and rapid growth of slash pine. This tree, 4 feet above the ground, was 54 inches in diameter and 9 annual rings were present at that height.

FIG. 8.-Stand of old timber, such as is rapidly disappearing. This is characterized by having wide sapwood and by producing very high yields under efficient management. Deep chipping (see figure 6) succeeded in this operation.

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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 saturated condition of dead and dried cells, especially the devitalized condition of the resiniferous parenchyma, that the presence of lightwood should be considered detrimental. Such a condition, moreover, 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 operations or from the statements of experienced operators, or are deductions 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 turpentine leases (page 25).

LOCATION AND SIZE OF THE FACES. 1

One of the most obvious sources of waste in turpentine operations, and apparently a matter which has received relatively little competent 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

portion to the size of the tree. (See pp. 29 to 31.) Conservative operators recommend leaving one-half, or at the very least one-third, of the bark uncut. Without such provision the tree is unduly injured and its productive power is reduced so that the yield is less or may even fail entirely, as shown in Plate VII, figure 3. The cost of turpentining such trees throughout the operation, or until they die, is, however, just as great in the matter of placing cups and aprons, chipping and dipping, as is the cost in the case of the more productive trees. Such trees are also frequently attacked, some think more often than more healthy individuals, by fungus or insects.30 Care is required not only with reference to the position of the faces in relation to each other, but also with regard to the way the tree leans, its general shape or curvature, and any special irregularities which may occur. Loss in production of oleoresin is also occasioned by cutting the first streaks too far above the ground. It is of advantage to place the faces as low as the butt conformation of the tree will permit.

The location of the faces with relation to the points of the compass has received some attention but appears to be considerably influenced by variable local conditions. As is shown in figures 1 to 6, the 15 trees selected at Columbia, Miss., where the position of the faces was noted, showed great variability in wood formation, with some tendency toward greater vigor on the south side. From some experiments with western yellow pine (Pinus ponderosa Laws.), it was found that an average from the total yields of 50 trees during one turpentining season was 9 per cent greater from the south side than from the north side cups.31 An experienced operator has advanced the following argument: 32

It is pretty well settled now that the average pine standing erect has thicker sap on the south side, evidence of greater thrift on that side; then, unless there are conditions that require it otherwise, it would seem to promise a larger yield of gum to so install the cup and chip as to leave as much of this best sap uncut as possible. Make the faces west or southwest, east or southeast. In cupping trees of the size to permit two cups, if the timber is to be cut for lumber before it has time to be recupped (or back cupped), place them opposite, east and west; but if it is expected to be cupped the second time, hang the cups southwest and southeast with 6 inches of unchipped surface between.

CONTAINERS FOR THE GUM.

The destructive method of using a box cut in the tree (Pl. I, fig. 1) to hold the gum has been practically abandoned. In its place are found a great variety of containers or cups of pottery or metal.

30 Hopkins, A. D., "The Southern Pine Bettle." Farmers' Bul. 1188, U. S. Dept. Agr., For.

1921.

31 Betts, H. S., "Possibilities of Western Pines as a Source of Naval Stores." Serv. Bul. 116.

Courtesy of Mr. A. Sessoms, Bonifay, Fla.

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