Status and conservation of the Palouse grassland in Idaho

Publication Type:

Unpublished

Authors:

Lichthardt, Juanita; Moseley, Robert K.

Source:

Idaho Department of Fish and Game, Boise, p.p. 28 + tables, maps, and appendixes (1997)

Call Number:

U97LIC03IDUS

Keywords:

endangered ecosystems, grasslands, Palouse Prairie

Abstract:

The Palouse Grassland is recognized as an ecologically distinct element of the Pacific Northwest Bunchgrass biome. The area once occupied by Palouse Grassland has seen nearly 100% conversion to cultivated agriculture, making it an imperiled ecosystem. Remnants of Palouse Grassland vegetation are now restricted to small areas on the edge of cultivated fields, or rocky slopes along the margin of the former prairie. The easternmost extent of the prairie region extends into Idaho, where three climax grassland associations have been described: Festuca idahoensis-Symphoricarpos albus (Idaho fescue-common snowberry), Festuca idahoensis-Rosa nutkana (Idaho fescue-Nootka rose), and Festuca scabrella-F. idahoensis (rough fescue-Idaho fescue). These communities, in turn, are habitats for six, globally rare plant species endemic to the region. This report documents the results of a 1996 survey of Palouse Grassland remnants in Idaho. Grassland communities were sampled, rare plant populations were documented, and grassland remnants were evaluated for their conservation value. Canopy cover data from plot sampling are summarized in a releve table. Stand composition is then evaluated in the context of plant associations recognized in the Western Regional Vegetation Classification for the study area. Researchers' data do not support the existence of two distinct vegetation zones in the Idaho portions of the prairie. Fourteen grassland sites with conservation value were identified and documented, noting their location, size, condition, biodiversity values, ownership and threats.