Report upon the forestry investigations of the of agriculture1877-1898 . tes the rate is slower, but remains longer on theincrease, while on good sites the maximum rate is soou course in a forest, where light conditions are not mostfavorable, because form development and soil conditions requireshade, the total wood formation is less than in an isolated tree favorably placed. Just so the domi-nant trees in a forest—i. e., those which have their crowns above all others—show, of course, theadvantage they have over the inferior trees which are suffering from the shade of t
Report upon the forestry investigations of the of agriculture1877-1898 . tes the rate is slower, but remains longer on theincrease, while on good sites the maximum rate is soou course in a forest, where light conditions are not mostfavorable, because form development and soil conditions requireshade, the total wood formation is less than in an isolated tree favorably placed. Just so the domi-nant trees in a forest—i. e., those which have their crowns above all others—show, of course, theadvantage they have over the inferior trees which are suffering from the shade of their , if we would take into consideration an entire forest growth, and determine, forinstance, how much wood an acre of such forest produces at different periods, we must not over-look the fact that the number of trees per acre changes as the trees grow older. Some of themare overshaded and crowded out by the others, so that a young growth of spruce might startwith 100,000 little seedlings to the acre, of which in the twentieth year only 10,000 would be alive,. Fk, s-M pi 276 FORESTRY INVESTIGATIONS U. S. DEPARTMENT OF AGRICULTURE. while in the fortieth year the uumber would be reduced to 1,200, aud in the hundredth year to280. Hence the rate of growth of any single tree gives no idea of what the acre of forest will do. Thus, while a single good white pine might grow the fastest in volume when about one hun-dred years old, then making wood at the rate of, say, cubic feet per year, an acre of pine ongood soil, containing about 1,600 trees, may make the most wood in the thirtieth year, thengrowing at the rate of 170 cubic feet per acre, while in the hundredth year the rate would notexceed 70 cubic feet; and an acre of pine in a poorer location, with about 1,400 trees, may makethe most wood in the fortieth year, at the rate of 100 cubic feet per acre. From the consideration of the relation of light conditions to soil conditions, to form develop-ment, and
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectforestsandforestry
