A Collection of Bulletins and Circulars, Issued for the Most Part by the U.S. Forest ServiceU.S. Government Printing Office, 1937 |
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acres annual bark billion feet blocks blue gum boom branches burned catalpa cent chain chestnut conifers cover creosoted crop crown cultivation Department of Agriculture diameter Douglas fir Engelmann spruce eucalypts European larch evaporation fire forest land Forest management Forest Service forestry form factor germination GIFFORD PINCHOT ground grow grown hardwoods haul heavy height growth hemlock honey locust hook humus inches increase larch less light load locust lodgepole pine Longleaf Pine lumber maple moisture nursery Osage orange pavement plantation planting pole production protection pruning rainfall red cedar Red Fir region reproduction road Rocky Mountain roots rows run-off saplings sapwood season seed beds seedlings Sewanee shade silvical skid sleds slopes soil southern species sprouts spruce stem stream stump surface thin timber tion transplanted trunk United usually western hemlock white pine wind wood yellow pine young trees
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Страница 12 - No public forest reservation shall be established, except to improve and protect the for'est within the reservation, or for the purpose of securing favorable conditions of water flows, and to furnish a continuous supply of timber for the use and necessities of citizens of the United States...
Страница 14 - In this way the bearing of trees toward heat and cold has a great deal to do with their distribution over the surface of the whole earth. Their distribution within shorter distances also often depends largely upon it. In the United States, for example, the Live Oak does not grow in Maine, nor the Canoe Birch in Florida. Even the opposite sides of the same hill may be covered with two different species, because one of them resists the late and early frosts and the fierce midday heat of summer, while...
Страница 12 - ... according to the following method until the time for planting in the field: Dig a trench deep enough to bury the roots and part of the stems. The trench should run east and west, with its south bank at a slope of about 30 degrees to the surface of the ground.
Страница 19 - Birch Trees which are found only, or most often, in pure forest are the social or gregarious kinds; those which grow in mixture with other trees are called scattered kinds. Most of the hardwood forests in the United States are mixed ; and many mixed forests, like that in the Adiroudacks, contain both broadPURE FOREST OF YOUNG RED FIR.
Страница 4 - Norway spruce, although it grows more rapidly on the better soils. The tree will grow well in a fresh, shallow, moderately porous soil, whether fertile or not, and will thrive with moderate moisture. It will not endure drought or a naturally dry soil. In common with our native spruces, this species is very shade enduring, forming dense stands which protect the soil and maintain forest conditions perfectly. The root system is shallow and not extensive. The growth during the...
Страница 13 - They made neither a durable pavement nor in any way a satisfactory one. But they were cheap and served a good purpose in tiding fast-growing cities over a critical period. There have also been laid in various cities pavements of oak, cypress, white pine, hemlock, Washington red cedar, cottonwood, mesquite, Osage orange, redwood, Douglas fir, and tamarack. In nearly all these cases the blocks were untreated, or at most dipped or boiled for a short time in tar, asphalt, or other mixture of supposed...