. Check list of the forest trees of the United States : their names and ranges. Forests and forestry; Trees. 20 and also by fine wavy concentric lines of short, thin-walled cells (see fig. 8 A), consists of thick-walled fibers (see dg. 8 B) and is the chief element of strength in oak wood. In good white oak it forms one-half and more of the wood; it cuts like horn, and the cut surface is shiny and of a deep chocolate brown color. In very narrow-ringed wood and in inferior red oak it is usually much reduced in quantity as well as quality. The pith rays of the oak, unlike those of conif
. Check list of the forest trees of the United States : their names and ranges. Forests and forestry; Trees. 20 and also by fine wavy concentric lines of short, thin-walled cells (see fig. 8 A), consists of thick-walled fibers (see dg. 8 B) and is the chief element of strength in oak wood. In good white oak it forms one-half and more of the wood; it cuts like horn, and the cut surface is shiny and of a deep chocolate brown color. In very narrow-ringed wood and in inferior red oak it is usually much reduced in quantity as well as quality. The pith rays of the oak, unlike those of coniferous woods, are at least in part very large and conspicuous (see fig. 6, their height indicated by the letter a, and their width by the letter h). The large medullary vays of oak are often twenty and more cells wide and several hundred cell rows in height, wliich amount com- monly to one or more inches. These large rays are consi)icuous on all sec- tions. They appear as long, sharp, grayish lines on the cross section, as short, thick lines, tapering at each end, on the tangential or "bastard" face, and as broad, shiny bands, the ^'mirrors," on the radial section. In addition to these coarse rays, there is also a large number of small pith rays, which can be seen only when magnitied. On the whole, the pith rays form a much larger part of the wood than might be supposed. In specimens of good white oak it has been lound that they formed about 16 to 25 per cent of the wood. >IINUTK STRUCTUKK. If a well-smoothed, thin disk, or cross section of oak (say one-sixteenth inch thick) is held up to the light, it looks very much like a sieve, the pores or vessels appearing as clean- cut holes; the spring wood and gray patches are seen to be (juite i)or- ous, but the firm bodies of fibers between them are dense and opaque. Examined with the magnifier it will be noticed that there is no such regularity of arrangement in straight rows as is conspicuous in the pine; on the co
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectforestsandforestry
