Bulletin (United States. Division of Forestry)

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U.S. Government Printing Office, 1904
 

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Էջ 17 - ... bleeding." This impairs the vigor of the root system, and consequently of the sprouts. Since sprouts are exceedingly brittle during the first year, timber cut in winter should be taken from the woods before sprouting begins in the spring; otherwise damage may be done. INFLUENCE OF AGE. Chestnut is a long-lived tree, attaining an age of 400 to 600 years. It seldom remains sound, however, to an old age. Trees over 100 years old begin to grow hollow in the center, though their growth in diameter...
Էջ 20 - The narrow vessels of the summer wood make it richer in wood substance than the spring wood composed of wide vessels. Therefore, rapid-growing specimens with wide rings have more wood substance than slow-growing trees with narrow rings. Since the more the wood substance the greater the...
Էջ 18 - Nevertheless, light is one of the factors influencing the reproduction of chestnut from seed, as is suggested by tJie fact that on the mixed type of chestnut and pine, where the density is less than on the two other types in which chestnut occurs, there are more trees from the seed (see Table IV,). Coppice chestnut is capable of enduring more shade than chestnut from the nut, contrary to European experience with coppice forests. Since sprouts start from stumps which have root systems already developed,...
Էջ 18 - W ?fi ffi •n 24 many sprouts while they are tender and brittle, leaving only about 6 of the most promising shoots on each stump. LIGHT REQUIREMENTS. The demands of chestnut upon light are moderate, at least during its youth, as is shown by its dense foliage and its capacity to come up under pine. Nevertheless, light is one of the factors influencing the reproduction of chestnut from seed, as is suggested by...
Էջ 15 - The height of the stump probably has some influence upon the place of sprouting, since the stumps that sprouted from their tops were, on an average, slightly higher than those that sprouted from the root collar only. The following table shows the relation between the height of the stump and the height of the predominating shoot when one year old : TABLE VI. — Relation between heiijht of stump and rigor of sprouts.
Էջ 25 - If the diameter breasthigh of a standing tree in the woods is known, its height and its diameter every 10 feet above the ground can be found in the table. It will be seen that the tops, and in large trees the butts, taper faster than the middle portions of the tree. The difference in taper between trees from seed and coppice is not sufficient to warrant distinction. TABLE XVI. — .Diameters ovimde bark at various heights.
Էջ 16 - Relation between cutting season and vigor of sprouts. The table makes it evident that winter is the best time for cutting trees if good coppice reproduction is desired. It shows that trees cut in winter produced sprouts 8 feet high during the first year, and 26 per cent of all sprouts were very thrifty, 51 per cent...
Էջ 25 - In many cases it is necessary to know the amount of bark to deduct in order to get the inside diameter, as, for instance, in cutting chestnut for telephone poles, which must be peeled and of specified dimensions. Therefore a table of the thickness of bark of trees of different Diameter breasthigh.
Էջ 26 - A table giving the diameter inside the bark at different heights above the ground can readily be made from the two preceding tables. It is interesting to compare the natural taper of chestnut with that required by specifications from telephone companies purchasing poles in the section of Maryland examined. TABLE XVIII.
Էջ 20 - ... more in diameter. In October this bur usually contains three shiny brown chestnuts, the central one of which is the most perfectly developed. The bark is smooth on young trees, but cracks and becomes rough with age. As a rule, sprouts have smoother bark than seedling trees of the same diameter (PL IV, figs.

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