Report upon the forestry investigations of the of agriculture1877-1898 . s them gradually, the stubs being iu time over-grown; finally, the second has a clear shaft, with a crown concentrated at the toj). while the first is beset with branches and branch stubs for its whole length (fig. 34).When ripped open lengthwise, the interior exhibits the condition shown in fig. 3G, the dead parts of the knot being indicated in heavier shading. Since the branches grow in more or less regular whorls, several knots, stumps, or limbs are met every (5 to 24 inches through the entire stem. Hence
Report upon the forestry investigations of the of agriculture1877-1898 . s them gradually, the stubs being iu time over-grown; finally, the second has a clear shaft, with a crown concentrated at the toj). while the first is beset with branches and branch stubs for its whole length (fig. 34).When ripped open lengthwise, the interior exhibits the condition shown in fig. 3G, the dead parts of the knot being indicated in heavier shading. Since the branches grow in more or less regular whorls, several knots, stumps, or limbs are met every (5 to 24 inches through the entire stem. Hence, in forest planting, trees are placed and kept for some time close together, in order to decrease the branching in the lower part of the tree and thus j)roduce a clean bole and clear lumber. Fio. 31 Section throngh a stem of beech, showing manner of bud and limbformation, a, dormant buds; 6, their traceof ])ith extending to the pith of the stem;c, a limb which started two years ago froma dormant bud; d, normal litnb; e, a limbdead for four years ; /. adventitiona F[Q. 32 Section through a partly decayed knot in oak wood, a, wood of the knot; b and c, wood cal-lus of thesfem covering the wound; shaded portion,decayed wood; black part, a cavity remaining. 272 FORESTRY INVESTIGATIONS U. S. DEPARTMENT OP AGRICULTURE. GROWTH IN THICKNESS. The young seedling and the young slioot of the older tree much resemble in interior structurethat of any herbaceous i3lant, being composed of a large amount of pith, loose squarish cells, anda few bundles of long fibers symmetrically distributed about the center, the whole covered with athin skin or epidermis. Bach strand or bundle of fibers, called fibro-vascular (fiber-vessel) bundles,consists of two kinds, namely, wood fibers on the inner side and bast fibers of different structureon the outer side. Between these two sets of fibers, the bast and the wood, there is a row of cellswhich form the really active, growing part of th
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectforestsandforestry
