. Ponderosa pine saplings respond to control of spacing and understory vegetation. Ponderosa pine; Ponderosa pine Spacing. Vegetation left CD Vegetation removed ° 1,000 — 500 -~ 250 125 62. 1,000 500 250 125 62 1,000 500 250 125 62 TREES PER ACRE AND SPACING (FEET) Figure annual volume increment of ponderosa pine saplings thinned to various spacings (1963-67). Bars show increment for total number of trees at each spacing. Points within bars show increment of the stated number of the largest well-distributed trees within the stand. produ
. Ponderosa pine saplings respond to control of spacing and understory vegetation. Ponderosa pine; Ponderosa pine Spacing. Vegetation left CD Vegetation removed ° 1,000 — 500 -~ 250 125 62. 1,000 500 250 125 62 1,000 500 250 125 62 TREES PER ACRE AND SPACING (FEET) Figure annual volume increment of ponderosa pine saplings thinned to various spacings (1963-67). Bars show increment for total number of trees at each spacing. Points within bars show increment of the stated number of the largest well-distributed trees within the stand. production rates for the same treatments and tree numbers. For example, there is little difference between the volume production of the "best" 250 trees in the 1,000-tree-per-acre treatment compared with that in a plot density of 250 trees. Similar conclusions can be drawn from other treatments and tree numbers. Evidently the growing space created by fewer and fewer trees was soon occupied by understory vegetation which offered as much competition or sometimes more than many more trees. This suggests that maximum benefits from thinning will be gained only by maintaining some suppression of understory vegetation for at least part of the life of the stand. Mortality Only 12 trees died of a total of 2,232. Two-thirds of this mortality occurred where 1,000 trees per acre were left and was due mostly to Armillaria root rot, although the Armillaria-CcLUsed mortality was not related to spacing. In terms of cubic volume, losses were extremely small. For example, the heaviest loss was at the spacing where vegeta- tion was left, and this amounted to only cubic foot per acre per year during the last period. Losses on the other treatments were cubic foot or less. No mortality took place during the first period. 11. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance o
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Keywords: ., bookcentury1900, bookcollectionbiodive, booksubjectponderosapine
