Palouse

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For other uses, see Palouse (disambiguation).

The Palouse is a region covering approximately 10,000 square miles of land in northwestern Idaho and southeastern Washington.

The Palouse region encompasses the rolling, fertile hills of the Palouse prairie, as well as the more southerly Camas Prairie and the forested hills and canyonlands of the area's rivers.

French trappers and explorers gave the region its present name, calling it Le Pelouse (roughly, "the grassland").

Contents

[edit] Geography

The Palouse Prairie lies at the eastern edge of the Palouse region, north of the Clearwater River. The Palouse region includes the following counties:

[edit] Geology

The peculiar and picturesque silt dunes which characterize the Palouse Prairie were formed during the ice ages (Alt and Hyndman 1989). Blown in from the glacial outwash plains to the west and south, the Palouse hills consist of more or less random humps and hollows. The steepest slopes, which may reach 50% slope, face the northeast. The highly productive loess ranges from 5 to 130 cm deep (Williams 1991). Large areas of level land are rare.

Higher elevations bordering the prairies such as the Palouse Range support an often dense coniferous forest.

[edit] Farming

Farming was extremely labor-intensive and still relied heavily on human and horse-power. An organized harvesting/threshing team in the 1920's required 120 men and 320 mules and horses (Williams 1991). Teams moved from farm to farm as the crops ripened. By this point, the combine had been invented and was in use, but few farmers had enough horses to pull such a machine, which required a crew of 40 horses and six men to operate on level ground. Because of this, use of combines on the Palouse lagged behind use in other farming communities in the United States.

It was only when the Idaho Harvester Company in Moscow, Idaho began to manufacture a smaller machine that combine harvesting became feasible. By 1930, 90% of all Palouse wheat was harvested using combines (Williams 1991).

The next step in mechanization was development of the tractor. As with the combines, the first steam engine and gasoline-powered tractors were too heavy and awkward for use on the steep Palouse hills. The smaller, general use tractors introduced in the 1920s were only marginally used. As late a s 1930, only 20% of Palouse farmers used tractors (Williams 1991).

[edit] Environment

Once an extensive prairie composed of mid-length perennial grasses such as bluebunch wheatgrass (Agropyron spicatum) and Idaho fescue (Festuca idahoensis), today virtually all of the Palouse Prairie is planted in agricultural crops. The native prairie is one of the most endangered ecosystems in the United States (Noss et al. 1995), as only a little over one percent of the original prairie still exists.

People have taken their toll on wildlife. Once abundant birds and small mammals are few. The intensive roadbed-to-roadbed farming practiced today across the Palouse leaves few fences and fewer fencerows. Many once intermittent streams are farmed; many perennial streams with large wet meadows adjacent to them are now intermittent or deeply incised.

Riparian areas offer breeding habitat for a greater diversity of birds than any other habitat in the U.S. (Ratti and Scott 1991). Loss of trees and shrubs along stream corridors means fewer birds and eventually fewer species. The majority of riparian areas have been lost across the bioregion.

Lately, conversion of agricultural lands to suburban homesites on large plots invites a new suite of biodiversity onto the Palouse Prairie. University of Idaho wildlife professor J. Ratti has documented changes in bird community composition over the past 10 years as he converted a wheat field into a suburban wildlife refuge. His 40 mile square yard now attracts 86 species of birds, an increase from 18.

Intensification of agriculture has affected both water quantity and quality. Agriculture has changed the bydrograph, increasing peak runoff flows and shortening the length of runoff. The result is more intense erosion and loss of perennial prairie streams. As early as the 1930s soil scientists were noting significant downcutting of regional rivers (Victor 1935) and expansion of channel width. Higher faster runoff caused streams to downcut quickly, effectively lowering the water table in immediately adjacent meadows. On the South Palouse River, this process was so efficient that by 1900 farming was possible where it had been too wet previously (Victor 1935). Replacement of perennial grasses with annual crops resulted in more overland flow and less infiltration, which translates at a watershed level to higher peak flows that subside more quickly than in the past. Once perennial prairie streams are now often dry by mid-summer. This has undoubtedly influenced the amphibious and aquatic species.

As population grew, towns and cities appeared changing the complexion of the area. By 1910, there were 22,000 people scattered in 30 communities across the Palouse Prairie.

Crop production increased dramatically (200 - 400%) after the introduction of fertilizer following World War II.

Since 1900, 94% of the grasslands and 97% of the wetlands in the Palouse Bioregion have been converted to crop, hay, or pasture lands. Approximately 63% of the lands in forest cover in 1900 are still forested, 9% are grass, and 7% are regenerating forestlands or shrublands. The remaining 21% of previously forested lands have been converted to agriculture or urban areas.

A farm in Whitman County, Washington
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A farm in Whitman County, Washington

The impacts of domestic grazers on the grasslands of the Palouse and Camas Prairies was transitory because much of the areas were rapidly converted to agriculture. However, the canyonlands of the Snake and Clearwater Rivers and their tributaries with their much shallower soils, steep topography, and hotter, drier climate, were largely unsuitable for crop production and were consequently used for a much longer period by grazing domestic animals (Tisdale 1986). There, intense grazing and other disturbances have resulted in irreversible changes with the native grasses largely replaced by annual grasses of the genus Bromus and noxious weeds, particularly from the genus Centaurea. The highly competitive plants of both of these genera evolved under similar climatic regimes in Eurasia and were introduced to the U.S. in the late 1800s.

[edit] Fires

While there is some debate over how frequently the Palouse prairie burned historically, there is consensus that fires are generally less frequent today than in the past, primarily due to fire suppression, construction of roads (which serve as barriers to fire spread) and conversion of grass and forests to cropland (Morgan et al. 1996). Historians recount lightning-ignited fires burning in the pine fringes bordering the prairies in late autumn, but the extent to which forest fires spread into the prairie or the converse is not known. Some fire ecologists believe the Nez Perce burned the Palouse and Camus Prairies to encourage growth of Camas (Morgan, pers. Comm); but there is little historical record to solve the mystery. European-American settlers used fire to clear land for settlement and grazing until the 1930s. Since then, forest fires have become less common. One result has been increasing tree density on forested lands and encroachment of shrubs and trees into previously open areas. Consequently, when fires occur in the forest, they are more likely to result in mixed severity or stand replacing events.

[edit] Trivia

[edit] See also

Spokane-Coeur d'Alene-Paloos War (Palouse War)

[edit] External links

[edit] Sources

As of this writing on May 25, 2004, most of the material in this article was copied from the following source: Chapter 10: Additional Figures - Biodiversity and Land-use History of the Palouse Bioregion: Pre-European to Present - Sisk, T.D., editor. 1998. Perspectives on the land-use history of North America: a context for understanding our changing environment. U.S. Geological Survey, Biological Resources Division, Biological Science Report USGS/BRD/BSR 1998-0003 (Revised September 1999).

The sources cited in this article are listed below:

  • Alt, D.D., and W. D. Hyndman. 1989. Roadside geology of Idaho. Mountain Press Publishing Company, Id. 403 pp.
  • Morgan, P., S.C. Bunting, A.E. Black, T. Merrill, and S. Barrett. 1996. Fire regimes in the Interior Columbia River Basin: past and present. Final Report, RJVA-INT-94913. Intermountain Fire Sciences Laboratory, USDA Forest Service, Intermountain Research Station, Missoula, Mont.
  • Noss, R.F., E.T. LaRoe III, and J.M. Scott. 1995. Endangered ecosystems of the United States: a preliminary assessment of loss and degradation. U.S. National Biological Service. Biological Report 28.
  • Ratti, J.T., and J.M. Scott. 1991. Agricultural impacts on wildlife: problem review and restoration needs. The Environmental Professional 13:263-274.
  • Tisdale, E.W. 1986. Canyon grasslands and associated shrublands of west-central Idaho and adjacent areas. Bulletin No. 40. Forestry, Wildlife and Range Experiment Station, University of Idaho, Moscow.
  • Victor, E. 1935. Some effects of cultivation upon stream history and upon the topography of the Palouse region. Northwest Science 9(3):18-19.
  • Williams, K.R. 1991. Hills of gold: a history of wheat production technologies in the Palouse region of Washington and Idaho. Ph.D. dissertation, Washington State University, Pullman.