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TIMBER TRENDS IN THE UNITED STATES 



Oak-Gum-Cypress. Bottom-land forests in which 

 tupelo, blackgum, sweetgum, oaks, or southern cypress, 

 singly or in combination, comprise a plurality of the 

 stocking except where pines comprise 25-50 percent, 

 in which case the stand would be classified oak-pine. 

 (Common associates include cottonwood, willow, ash, 

 elm, hackberry, and maple.) 



Elm-Ash-Cottonwood. Forests in which elm, ash, or 

 cottonwood, singly or in combination, comprise a 

 plurality of the stocking. (Common associates include 

 willow, sycamore, beech, and maple.) 



Maple-Beech-Birch. Forests in which maple, beech, 

 or yellow birch, singly or in combination, comprise a 

 plurality of the stocking. (Common associates include 

 hemlock, elm, basswood, and white pine.) 



Aspen-Birch. Forests in which aspen, balsam poplar, 

 paper birch, or gray birch, singly or in combination, 

 comprise a plurality of the stocking. (Common asso- 

 ciates include maple and balsam fir.) 



Major Western Forest Type Groups: 



Douglas-fir. Forests in which Douglas-fir comprise a 

 plurality of the stocking. (.Common associates include 

 western hemlock, western redcedar, the true firs, red- 

 wood, ponderosa pine, and larch.) 



Hemlock-Sitka Spruce. Forests in which western 

 hemlock and/or Sitka spruce comprise a plurality of the 

 stocking. (Common associates include Douglas-fir, 

 silver fir, and western redcedar.) 



Redwood. Forests in which redwood comprises a 

 plurality of the stocking. (Common associates include 

 Douglas-fir, grand fir, and tanoak.) 



Ponderosa Pine. Forests in which ponderosa pine 

 comprises a plurality of the stocking. (Common asso- 

 ciates include Jeffrey pine, sugar pine, limber pine, 

 Arizona pine, Apache pine. Chihuahua pine, Douglas- 

 fir, incense cedar, and white fir.) 



Western White Pine. Forests in which western white 

 pine comprises a plurality of the stocking. (Common 

 associates are western redcedar, larch, white fir, Douglas- 

 fir, lodgepole pine, and Engelmann spruce.) 



Lodgepole Pine. Forests in which lodgepole pine 

 comprises a plurality of the stocking. (Common asso- 

 ciates are alpine fir, western white pine, Engelmann 

 spruce, aspen, and larch.) 



Larch. Forests in which western larch comprises a 

 plurality of the stocking. (Common associates are 

 Douglas-fir, grand fir, westerji redcedar, and western 

 white pine.) 



Fir-Spruce. Forests in which true firs (Abies spp.), 

 Engelmann spruce, or Colorado blue spruce, singly or 

 in combination, comprise a plurality of the stocking. 

 (Common associates are mountain hemlock and lodge- 

 pole pine.) 



Hardwoods. Forests in which aspen, red alder, or 

 other western hardwoods, singly or in combination, 

 comprise a plurality of the stocking. 



Chaparral. Forests of heavily branched dwarfed trees 

 or shrubs, usually evergreen, the crown canopy of which 

 at maturity covers more than 50 percent of the ground 

 and whose primary value is watershed protection. The 

 more common chaparral constituents are species of 

 Quercus, Cercocarpus, Garrya, Ceanothus, Ardostaphylos, 

 and Adenostoma. (Types dominated by such shrubs as 

 Artemisia, Opuntia, Purshia, Gutierrezia, or semidesert 

 species are not commonly considered chaparral.) 



Pinyon-Juniper. Forests in which pinyon pine and/or 

 juniper comprise a plurality of the stocking. 



Gross National Product (GNP). The total value of all 

 goods and services produced in the Nation during a 

 specified period. 



Growing Stock Volume. Net volume in cubic feet of 

 live sawtimber and poletimber trees from stump to a 

 minimum 4-inch top (of central stem) outside bark or to 

 the point where the central stem breaks into Hmbs. 



Growing-Stock Trees. Live sawtimber trees, pole- 



timber trees, saplings, and seedlings meeting specified 

 standards of quality or vigor; excludes cull trees. 



Growth. See definitions for "Net annual growth" and 

 "Ingrowth." 



Hardwoods. Dicotyledonous trees, usually broad- 

 leaved and deciduous. 



Household. A household consists of all the persons 

 occupying a dwelling unit. 



Indian Lands. Tribal lands held in fee by the Federal 

 Government but administered for Indian tribal groups, 

 and Indian trust allotments. 



Industrial Wood. All commercial roundwood products 

 except fuelwood. 



Industrial Raw Materials. Includes a variety of (a) 

 agricultural nonfoods and wildlife products, such as 

 cotton and other fibers, vegetable oils, hides, rubber and 

 furs, (b) minerals except gold, such as iron and other 

 metallic ore, clay, sand limestone, and sulfur, and (c) 

 timber products such as saw logs, veneer logs, and pulp- 

 wood. 



Ingrowth. The number or net volume of trees that 

 grew into the 6-inch diameter class or into sawtimber size 

 classes during a specified period. 



Labor Force. That section of the population 14 years 

 of age and older that is or could be expected to be: (a) 

 productively engaged in civilian economic activity, (b) 

 serving in the Nation's armed forces, and (c) out of 

 employment but available for and willing to accept 

 employment. 



Land Area. Census definition: The area of dry land 

 and land temporarily or partially covered by water such as 

 marshes, swamps, and river flood plains (omitting tidal 

 flats below mean high tide) ; streams, sloughs, estuaries, 

 and canals less than \i of a statute mile in width; and lakes, 

 reservoirs, and ponds less than 40 acres in area. Forest 

 Survey definition: Same as above except minimum width 

 of streams, etc. is 120 feet and minimum size of lakes, etc. 

 is 1 acre. 



Log Grades. A classification of logs based on external 

 characteristics as indicators of quality or value. 



Logging Residues. The unused portions of poletimber 

 and sawtimber trees killed by land clearing, cultural opera- 

 tions, or timber harvesting. 



Miscellaneous Federal Land. Federal land other than 

 national forests, lands administered by Bureau of Land 

 Management, and Indian lands. 



Miscellaneous Private Land. Privately owned lands 

 other than forest industry or farmer-owned lands. 



Mortality. The volume of sound wood in live sawtimber 

 and poletimber trees dying from natural causes during a 

 specified period. 



National Forest Land. Federal lands which have been 

 designated by Executive order or statute as national forests 

 or purchase units, and other lands under the administration 

 of the Forest Service, including experimental areas and 

 Bankhead-Jones title III lands. 



Net Annual Growth. The annual change in volume of 

 sound wood in live sawtimber and poletimber trees 

 resulting from natural causes. 



Net Volume in Board Feet: The gross board-foot 

 volume of trees less deductions for rot or other defect 

 affecting use for lumber. 



Net Volume in Cubic Feet. Gross volume in cubic feet 

 less deductions for rot. 



Noncommercial Forest Land. Unproductive forest land 

 incapable of yielding crops of industrial wood because of 

 adverse site conditions, and productive forest land with- 

 drawn from commercial timber use through statute or 

 administrative regulation. 



Nonforest Land. Land that has never supported forests 

 and lands formerly forested but now developed for non- 

 forest uses such as crops, improved pasture, residential 

 areas, city parks, improved roads, and adjoining rights-of- 

 way, power-line clearings, and certain areas of water classi- 

 fied by the Bureau of the Census as land. (See definition 

 for land area.) In forest areas unimproved roads, streams, 



