No abstract

Consequences of treating Wyoming big sagebrush to enhance wildlife habitats. Rangeland Ecology & Management, 65(5), 444-455.

Four Wyoming big sagebrush (Artem& tri&nW ssp. wyomingends Beetle and Young) control treatments: burning, spraag with 2,4-D, rotocutting, and plowing, along with no control (rest) were compared in southwestern Montana. Production date (excluding sagebrush) were collected 10 years and sagebrush canopy cover and understory basal cover were collected 8 years during the period 1963-1981. Sagebrush canopy was most effectively reduced by burning while plowing with seeding was least effective. Rest alone resulted in a 29% reduction In sagebrush canopy during the study period. By 1981, burning provided the most production from the dominant forage species (bluebunch wheatgrass (Agropyron @catum (Pursh) Scribn.) and important vegetal classes, although buming and spraying were equally successful when production was totaled for all years sampled. Understory basal cover did not prove useful to evaluate treatment effectiveness.

Samples of current year's growth of leaves and stems were collected in February 1983 from basin big sagebrush (Artemisia tridcntotoNuit.-), Wyoming big sagebrush (A. t. wyomingensis Beetle and Young), mountain big sagebrush (A.t. vaseyana [Rydb.] Rectle), and black sagebrush (A. nova Nels.) on a mule deer (Odocoikushemionushemionu) winter range near Cardiner, Montana. Samples were from both lightly and heavily used plants (form classes) within each taxon. Crude terpenoids were separated into 3 groups: beadspace vapors, volatile, and nonvolatile crude terpenoids. Compounds in each group are thought to stimulate the sensory organs of mule deer. Individual compounds were identified and quantified for comparison with preference ranks among taxa and between utilixation form classes. Seven compounds were selected by discrhnlnant analysis as indicators among the 4 taxa, with methacrolein+ethanol, p-cymene, and the smquiterpene lactones the most probable preference determinants. Seven other compounds were found useful for separating plants within taxa into form classes. Chemical differences between the 2 form classes, however, were less distinguishable than were those among the 4 taxa.

No abstract