Usda forest service pacific northwest research station research paper

Usda forest service pacific northwest research station research paper

Christmas tree cultivation is an agricultural, forestry, and horticultural occupation which involves growing pine, spruce, and fir trees specifically for use as Christmas trees.. The first Christmas tree farm was established in , but most consumers continued to obtain their trees from forests until the s and s. Christmas tree farming was once seen only as a viable alternative for Decaying organic materials and soil quality in the Inland Northwest: a management opportunity. Gen. Tech. Rep. INT Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station. 15 p. Heilman, P. E.; Gessel, S. P. Nitrogen requirements and the biological cycling of nitrogen in Douglas-fir stands in Pinus ponderosa, commonly known as the ponderosa pine, bull pine, blackjack pine, western yellow-pine, or filipinus pine is a very large pine tree species of variable habitat native to mountainous regions of western North blogger.com is the most widely distributed pine species in North America.: 4 Pinus ponderosa grows in various erect forms from British Columbia southward and eastward through

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Douglas-fir Pseudotsuga menziesiialso called red-fir, Oregon-pine, Douglas-spruce, and piño Oregon Spanishis one of the world's most important and valuable timber trees. It has been a major component of the forests of western North America since the mid-Pleistocene Although the fossil record indicates that the native range of Douglas-fir has never extended beyond western North America, the species has been successfully introduced in the last years into many regions of the temperate forest zone Two varieties of the species are recognized: P.

menziesii Mirb. Franco var. menziesii, called coast Douglas-fir, and P. menziesii var. glauca Beissn. Franco, called Rocky Mountain or blue Douglas-fir. The latitudinal range of Douglas-fir is the greatest of any commercial conifer of western North America. Its native range, extending from latitude 19° to 55° N. From the apex in central British Columbia, the shorter arm extends south along the Pacific Coast Ranges for about km 1, mi to latitude 34° 44' N.

Nearly pure stands of Douglas-fir continue south from their northern limit on Vancouver Island through western Washington, Oregon, and the Klamath and Coast Ranges of northern California as far as the Santa Cruz Mountains.

In the Sierra Nevada, Douglas-fir is a common part of the mixed conifer forest as far south as the Yosemite region. The range of Douglas-fir is fairly continuous through northern Idaho, western Montana, and northwestern Wyoming. Several outliers are present in Alberta and the eastern-central parts of Montana and Wyoming, the largest being in the Bighorn Mountains of Wyoming.

In northeastern Oregon, and from southern Idaho south through the mountains of Usda forest service pacific northwest research station research paper, Nevada, Colorado, New Mexico, Arizona, extreme western Texas, and northern Mexico, the distribution becomes discontinuous. Douglas-fir grows under a wide variety of climatic conditions table 1. The coastal region of the Pacific Northwest has a maritime climate characterized by mild, wet winters and cool, relatively dry summers, a long frost-free season, and narrow diurnal fluctuations of temperature 6° to 8° C; 43° to 46° F.

Precipitation, mostly as rain, is concentrated in the winter months. Climate in the Cascade Range and Sierra Nevada tends to be more severe. Altitude has a significant effect on local climate. In general, temperature decreases and precipitation increases with increasing elevation on both western and eastern slopes of the mountains. Winters are colder, frost-free seasons are shorter, and diurnal fluctuations of temperature are larger 10° to 16° C; 50° to 61° F.

Much of the precipitation is snow. In the northern Rocky Mountains, Douglas-fir grows in a climate with a marked maritime influence. Mild continental climate prevails in all seasons, except midsummer.

Precipitation is evenly distributed throughout the year, except for a dry period usda forest service pacific northwest research station research paper July and August.

In the central Rocky Mountains, the climate is continental. Winters are long and severe; summers are hot and in some parts of the region, very dry. Annual precipitation, higher on the western sides of the mountains, is mainly snow. Rainfall patterns for the southern Rocky Mountains generally show low winter precipitation east of usda forest service pacific northwest research station research paper Continental Divide but high precipitation during the growing season.

West of the Continental Divide, the rainfall is more evenly divided between winter and summer. Frost may occur in any month in the northern part of the range. Length of frost-free periods, however, varies within the central and southern Rocky Mountain regions, even at the same elevations. The variety menziesii of Douglas-fir reaches its best growth on well-aerated, deep soils with a pH range from 5 to 6. It will not thrive on poorly drained or compacted soils. Soils in the coastal belt of northern California, Oregon, and Washington originated chiefly from marine sandstones and shales with scattered igneous intrusions, usda forest service pacific northwest research station research paper.

These rocks have weathered deeply to fine-textured, well-drained soils under the mild, humid climate of the coast. Surface soils are generally acid, high in organic matter and total nitrogen, and low in base saturation.

Soils in the Puget Sound area and in southwestern British Columbia are almost entirely of glacial origin. Soils farther inland within the range of the variety menziesii are derived from a wide variety of parent materials, usda forest service pacific northwest research station research paper.

These include metamorphosed sedimentary material in the northern Cascades and igneous rocks and formations of volcanic origin in the southern Cascades.

Depth of soils ranges from very shallow on steep slopes and ridgetops to deep in deposits of volcanic origin and residual and colluvial materials. Texture varies from gravelly sands to clays. Surface soils are in general moderately acid.

Their organic matter content varies from moderate in the Cascade Range to high in portions of the Coast Range and Olympic Peninsula. Total nitrogen content varies considerably but is usually low in soils of glacial origin. Great soil groups characteristic of the range of coastal Douglas-fir include Haplohumults Reddish Brown Lateritics of the order Ultisols, Dystrochrepts Brown LateriticsHaplumbrepts Sols Bruns Acides of the order Inceptisols, Haplorthods Western Brown Forest soils of the order Spodosols, Xerumbrepts Brown Podzolic soilsand Vitrandepts Regosols Soils within the range of Rocky Mountain Douglas-fir originated also from a considerable array of parent materials.

In south-central British Columbia, eastern Washington, and northern Idaho, soils vary from basaltic talus to deep loess with volcanic ash to thin residual soil over granitic or sedimentary rocks. They are mostly Vitrandepts and Xerochrepts. Parent materials in Montana and Wyoming consist of both igneous and sedimentary rocks, and locally of glacial moraines. Soils derived from noncalcareous substrates are variable in texture but usda forest service pacific northwest research station research paper gravelly and acidic.

A significant portion of the sedimentary rocks is limestone, which gives rise to neutral or alkaline soils ranging in texture from gravelly loams to gravelly silts.

Limestones often weather into soils that are excessively well drained. Soils are Cryoboralfs of the order Alfisols, and Cryandepts and Cryochrepts of the order Inceptisols, usda forest service pacific northwest research station research paper. Soils in the central and southern Rocky Mountains are very complex. They developed from glacial deposits, crystalline granitic rocks, conglomerates, sandstones, and, in the Southwest, limestones.

These soils are Alfisols Gray Wooded soilsMollisols Brown Forest soilsSpodosols Brown Podzolic soils, Podzolsand Entisols 2, Altitudinal distribution of both varieties of Douglas-fir menziesii and glauca increases from north to south, reflecting the effect of climate on distribution of the species.

The principal limiting factors are temperature in the north of the range and moisture in the south. Consequently, Douglas-fir is found mainly on southerly slopes in the northern part of its range, and on northerly exposures in the southern part.

At high elevations in the southern Rocky Mountains, however, Douglas-fir grows on the sunny slopes and dry rock exposures Generally, the variety glauca grows at considerably higher altitudes than the coastal variety of comparable latitude. Altitudinal limit for Douglas-fir in central British Columbia is about m 2, ft but rises to m 4, ft on Vancouver Island.

In Washington and Oregon, the species generally occurs from sea level to m 5, ftalthough locally it may occur higher. In the southern Oregon Cascades and in the Sierra Nevada, the altitudinal range is between and m 2, usda forest service pacific northwest research station research paper, and 6, ft.

In river valleys and canyon bottoms, the species may occasionally occur at elevations of to m to ft. Near the southern limit of its range in the Sierra Nevada, the species grows to elevations of m 7, ft.

The inland variety grows at elevations from to m 1, to 8, ft in the northern part of its range. In the central Rocky Mountains, Douglas-fir grows mostly at elevations between and m 6, and 8, ftand in the southern Rocky Mountains, between and m 8, and 9, ft.

In some localities in southern and central Arizona, Douglas-fir may be found as low as m 5, usda forest service pacific northwest research station research paper, ft in canyon bottoms. The highest elevation at which Douglas-fir grows in the Rocky Mountains is m 10, ft on the crest of Mount Graham in southeastern Arizona. Periodic recurrence of catastrophic wildfires created vast, almost pure stands of coastal Douglas-fir throughout its range north of the Umpqua River in Oregon.

Although logging has mainly eliminated the original old-growth forest, clearcutting combined with slash burning has helped maintain Douglas-fir as the major component in second-growth stands. Where regeneration of Douglas-fir was only partially successful or failed, red alder Alnus rubra has become an associate of Douglas-fir or has replaced it altogether.

Rocky Mountain Douglas-fir grows in extensive pure stands, uneven- and even-aged, in southern Idaho and northern Utah and in western Montana as a broad belt between ponderosa pine and spruce-fir zones. At high elevations or northerly latitudes, more cold-tolerant mountain hemlock Tsuga mertensianawhitebark pine Pinus albicaulistrue firs Abies spp.

Douglas-fir yields to ponderosa pine P. ponderosaincense-cedar Libocedrus decurrensOregon white oak Quercus garryanaCalifornia black oak Q. kelloggiicanyon live oak Q.

chrysolepisand interior live oak Q. wislizeni on droughty sites, and to western redcedar Thuja plicatamaples Acer spp. Toward the fog belt of the Pacific coast, Douglas-fir gives way to Sitka spruce Picea sitchensiswestern hemlock Tsuga heterophyllaand western redcedar. The variety menziesii is a major component of four forest cover types 20 : Pacific Douglas-Fir Society of American Foresters TypeDouglas-Fir-Western Hemlock TypePort Orford-Cedar Typeand Pacific Ponderosa Pine-Douglas-Fir Type It is a minor component of the following types:.

The variety glauca is a principal species in three forest cover types: Interior Douglas-Fir TypeWestern Larch Typeand Grand Fir Type It is a minor species in five types: Engelmann Spruce-Subalpine Fir TypeWhite Fir TypeWestern White Pine TypeAspen Typeand Lodgepole Pine Type Wherever Douglas-fir grows in mixture with other species, the proportion may vary greatly, depending on aspect, usda forest service pacific northwest research station research paper, kind of soil, and the past history of an area, especially as it relates to fire.

This is particularly true of the mixed conifer stands in the southern Rocky Mountains where Douglas-fir is associated with ponderosa pine, southwestern white pine Pinus strobiformiscorkbark fir Abies lasiocarpa var. arizonicawhite fir Abies concolorblue spruce Picea pungensEngelmann spruce, and aspen Populus spp. The most important shrubs associated with coastal Douglas-fir 21 through its central and northern range are vine maple Acer circinatumsalal Gaultheria shallonPacific rhododendron Rhododendron macrophyllumOregongrape Berberis nervosared huckleberry Vaccinium parvifoliumand salmonberry Rubus spectabilis.

Toward the drier southern end of its range, common shrub associates are California hazel Corylus cornuta var. californicaoceanspray Holodiscus discolorcreeping snowberry Symphoricarpos molliswestern poison-oak Toxicodendron diversilobumceanothus Ceanothus spp. Principal understory species associated with variety glauca differ within its range 3. In the northern part, they are common snowberry Symphoricarpos albuswhite spirea Spirea betulifolianinebark Physocarpus malvaceusand pachistima Pachistima myrsinites.

In the central part, they are true mountain-mahogany Cercocarpus montanussquaw currant Ribes cereumchokeberry Prunus virginianabig sagebrush Artemisia tridentatawestern serviceberry Amelanchier alnifoliaand bush rockspirea Holodiscus dumosus ; in the southern part they are New Mexico locust Robinia neomexicanaRocky Mountain maple Acer glabrumand oceanspray 3.

Nature and Health Speaks: GirlTrek, Washington Trails Association, USDA Forest Service

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THE EFFECT OF FIRE ON SOIL PROPERTIES

Pinus ponderosa, commonly known as the ponderosa pine, bull pine, blackjack pine, western yellow-pine, or filipinus pine is a very large pine tree species of variable habitat native to mountainous regions of western North blogger.com is the most widely distributed pine species in North America.: 4 Pinus ponderosa grows in various erect forms from British Columbia southward and eastward through Christmas tree cultivation is an agricultural, forestry, and horticultural occupation which involves growing pine, spruce, and fir trees specifically for use as Christmas trees.. The first Christmas tree farm was established in , but most consumers continued to obtain their trees from forests until the s and s. Christmas tree farming was once seen only as a viable alternative for USDA Forest Service, Research Paper PNW Pacific Northwest Forest and Range Experiment Station, Portland, OR. 18 p. Barrett, James W., and Lewis F. Roth. Response of dwarf mistletoe-infested ponderosa pine to thinning: 1. Sapling growth.