Environmental Factors Related to Medusahead Distribution

Abstract

Sites particularly susceptible to medusahead invasion in the more arid portions of Idaho were either those with well-developed soil profiles, particularly those with high clay content either at or near the surface; or those occupying topographic positions that received additional runoff from adjacent sites. In more mesic climates moderately well developed soils appeared as highly susceptible as the well-developed soils. Conversely, soils with little profile development, particularly those which were well drained, remained dominated by cheatgrass in early seral stages regardless of whether they were in the more arid or mesic areas. The nature of the surface geology as it influenced the soil texture derived therefrom was a valuable aid to identifying sites susceptible to medusahead. Maintaining a good stand of perennial vegetation appeared the best barrier to medusahead invasion in to susceptible soils.

First-Year Establishment, Biomass and Seed Production of Early vs. Late Seral Natives in Two Medusahead (Taeniatherum caput-medusae) Invaded Soils

“…Our data support observations and suggestions that medusahead is a highly competitive plant (Davies and Svejcar 2008;Young 1992;Young and Mangold 2008), capable of expanding its current range (Dahl and Tisdale 1975;Johnson and Davies 2012;Young 1992). Establishment of medusahead was slightly but significantly higher on the sandy loam, but it was high in all treatments (ranging from 83 to 93%; Figure 2a).…”

“…It appears that medusahead invasion is most closely associated with fine-textured to moderately fine-textured soils, including clays and clay loams (Dahl and Tisdale 1975;Young and Evans 1970), which may be related to differences in water holding capacity. However, limited observations have suggested that medusahead is capable of expanding its current range into more coarse-textured soils (Dahl and Tisdale 1975;Young 1992), demonstrating the need for restoration studies that compare plant performance in different soil types.…”

Genetic structure of Greater Sage-Grouse (Centrocercus urophasianus) in a declining, peripheral population

“…These communities include low sagebrush and mountain big sagebrush communities as well as some Wyoming big sagebrush communities. One common feature among these communities is the presence of a clay horizon in the soil (Dahl and Tisdale 1975).…”

Plant–soil relationships of the invasive annual grass Taeniatherum caput-medusae: a reciprocal transplant experiment

“…It spread rapidly in the 1930s (Young and Evans 1982) and has become a major invasive species across millions of hectares on clayrich, arid to semi-arid rangelands of the western United States (Young and Evans 1970;Dahl and Tisdale 1975). Taeniatherum caput-medusae, like the invasive annual grass Bromus tectorum L., increases the risk and scale of catastrophic wildfires (D' Antonio and Vitousek 1992).…”