Habitat Differences between Basin and Wyoming Big Sagebrush in Contiguous Populations

Abstract

Basin and Wyoming big sagebrush plants growing in contiguous populations were studied to identify potential habitat differences in plant water and soil relationships. At 3 study sites, basin big sagebrush plants were growing in and adjacent to a drainage, while Wyoming big sagebrush plants occupied areas adjacent to the basin big sagebrush populations. Soil-and leaf-water potentials and leaf-transpiration resistances were measured from May to October 1980 to identify differences between basin and Wyoming big sagebrush plant-water relationships. Soil identification and plant tissue analyses were conducted to help characterize edaphic differences between the subspecies. The results of these studies showed that basin big sagebrush plants grew in a more mesic and fertile habitat than did Wyoming big sagebrush plants. Understanding the environmental differences of these two big sagebrush subspecies is important in effectively managing basin and Wyoming big sagebrush ranges. The woody sagebrushes (subgenus tridentatae (Rhdb.) E.D. McArthur of Artemisia L.) occur naturally only in western North America, ranging from southern Canada to northern Mexico (Beetle 1960, McArthur et al. I98 I). The most common, important, and widely distributed species is big sagebrush (Artemisia tridentata Nutt.). Big sagebrush plants are common on about 58,655,OOO hectares from the arid lands of the Great Basin to the moist, cool areas of mountain ranges (Beetle 1960, Hall and Clements 1923, McArthur 1979, Winward 1970). Considering the wide distribution of big sagebrush, it is not surprising to find genotypic variation among A. tridentata populations (Caldwell 1979). Presently, the big sagebrush complex consists of 3 subspecies with 2 forms (Beetle 1960, Beetle and Young Authors are range ecologist,

Environmental and vegetation relationships of the Artemisia tridentata spp. wyomingensis alliance

“…Other studies have also reported that soil characteristics affected species composition in the Artemisia steppe (Anderson, 1956;Barker and McKell, 1983;Jensen et al, 1990;Lentz and Simonson, 1987a, b;Passey et al, 1982;Shumar and Anderson, 1986;Swanson et al, 1986). Similar to our findings, several studies reported that soil texture (Jensen et al, 1990;Shumar and Anderson, 1986;Swanson et al, 1986) and soil nitrogen (Barker and McKell, 1983;Jensen et al, 1990) influenced plant species composition in the Artemisia steppe. Unlike our study, these previous efforts did not report total soil carbon or depth to a Bt horizon as associated with plant species composition.…”

“…Also in contrast to our results, previous studies reported that numerous other soil characteristics were associated with variation in plant species composition. However, the discrepancies in findings are due to previous studies investigating the influence of soil factors on only dominant species (Anderson, 1956;Barker and McKell, 1983;Jensen et al, 1990;Lentz and Simonson, 1987a, b;Passey et al, 1982;Shumar and Anderson, 1986;Swanson et al, 1986), whereas our research investigated soil factors influence on community composition. Slope was the only non-soil factor we found to be at least moderately correlated with plant species composition.…”

“…wyomingensis alliance was selected because it is the most extensive, least resilient to disturbance, most endangered of the A. tridentata Nutt. (big sagebrush) complex in the Intermountain West (Barker and McKell, 1983;Beetle and Young, 1965;McArthur and Plummer, 1978;Miller and Eddleman, 2000;Morris et al, 1976;Tisdale, 1994;West et al, 1978), and the alliance occurs within a relatively narrow band (180-300 mm) of precipitation (Goodrich et al, 1999;Tisdale, 1994). By focusing on the A. tridentata spp.…”

Fine-scale variation of historical fire regimes in sagebrush-steppe and juniper woodland: an example from California, USA

“…texture, depth to clay layers and total depth), microtopography (i.e. concave, convex) and incident radiation (a function of slope and aspect) vary across space and influence the spatial heterogeneity of vegetation (West et al 1978;Passey et al 1982;Barker and McKell 1983;Jensen et al 1990;Johnson and Miller 2006;Davies et al 2007). These drivers can vary at fine spatial scales (tens to thousands of hectares), and so fire regimes likely varied at similarly fine scales across sagebrush-steppe and juniper woodlands in the Intermountain West, as they have in other more mesic forested plant communities (e.g.…”

Vegetation Characteristics Across Part of the Wyoming Big Sagebrush Alliance

“…Management objectives also need to be tailored to the individual subspecies of the big sagebrush complex because of differing environmental characteristics influencing vegetation structure and composition, varying responses to grazing and other disturbances, and differing resistance to weed invasion (Beetle and Young 1965;Morris et al 1976;Winward and Tisdale 1977;Hironaka 1978;McArthur and Plummer 1978;Blaisdell et al 1982;Barker and McKell 1983).…”