. Journal of forestry . Firewood, Firewood,Pli)t Arc No. tiooi Saw timber, bd. ft. cds. cds. II _u 4^4 32,320 (pine, 85 percent) HI 40 368 17,356 (pine, 75 per cent) I\ 30 ii2 16,064 (pine, 60 per cent) III Iahle 5 are stated the liiial yields for each of the tlirce plots onan acre basis, including the vohime oi wood in cords derivedfrom the improvement ctilling. which, under average market con- 502 JOURNAL OF FORESTRY ditions, would more than pay for the operation. For simplicity allspecies yielding saw timber were thrown together, but the per cent ofth
. Journal of forestry . Firewood, Firewood,Pli)t Arc No. tiooi Saw timber, bd. ft. cds. cds. II _u 4^4 32,320 (pine, 85 percent) HI 40 368 17,356 (pine, 75 per cent) I\ 30 ii2 16,064 (pine, 60 per cent) III Iahle 5 are stated the liiial yields for each of the tlirce plots onan acre basis, including the vohime oi wood in cords derivedfrom the improvement ctilling. which, under average market con- 502 JOURNAL OF FORESTRY ditions, would more than pay for the operation. For simplicity allspecies yielding saw timber were thrown together, but the per cent ofthe total represented by white pine is shown in each case in figures show that the final yield of saw timber, at least on sandysoil, can be nearly tripled by a release cutting made about the twentiethyear, and that thereafter the possibility of improving the final yieldgrows rapidly less. The figures do not indicate, however, what may beexpected from proper cuttings made before the twentieth year, although. Fig. 3.—Bven-aged sapling stand tivo years after second weedingSpecies mainly white ash, red oak, and white pine. Forest weeds finally eliminated. the obvious presumption is that an earlier cutting would produce a stillbetter result, especially on the better soils. In stands less than twentyyears old, where the effect of competition in height growth has not socompletely declared itself, it is very difficult to make a crown classifica-tion on which a specific calculation of yield can safely be based. Never-theless, it is possible to get a definite idea of the possibilities of earlierforest weeding by reference to operations and experiments carried outin young growth less than ten years old. The destructive competition that takes place in a young mixed standis not solely a matter of worthless species against desirable species or YIELD OF VOLUXTKEK SECOND CKOWTII oO.] of rapid-growing against slow-growing trees. It is a matter of faultyphysical arrangement of th
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectforestsandforestry
