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Full-Text Articles in Plant Sciences
Livestock As Seed Disseminators For Reseeding Degraded Rangelands: The Role Of Dung In Gap Formation And Plant Establishment, Brian S. Auman
Livestock As Seed Disseminators For Reseeding Degraded Rangelands: The Role Of Dung In Gap Formation And Plant Establishment, Brian S. Auman
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Livestock (cattle and sheep) were examined as seed disseminators for reseeding degraded Intermountain rangelands. "Hycrest" crested wheatgrass [Agropyron desertorum (Fisch. ex Link) Schult. X A. cristatum (L.) Gaert.] seed was fed to yearling Holstein steers and Suffolk ewes. Dung was collected from each animal type and deposited on plots of high and low densities of an annual [cheatgrass (Bromus tectorum L.)] and perennial [squirreltail (Sitanion hystrix Nutt.)] grass species. The experiment evaluated the ability of the dung to suppress the resident vegetation, and the recruitment and establishment of Hycrest seedlings emerging from the dung.
Sheep dung had …
Ecological Amplitude And Invasion Of Diffuse Knapweed At Yakima Training Center, Washington, Donna Denise Wilcox
Ecological Amplitude And Invasion Of Diffuse Knapweed At Yakima Training Center, Washington, Donna Denise Wilcox
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Diffuse knapweed (Centaurea diffusa) is an introduced annual or short-lived perennial from Eurasia that has become a threat to native rangelands in the Pacific Northwest. Military training activities on the Yakima Training Center (YTC) increase the likelihood that knapweed will expand its range at YTC. This study, conducted in a major watershed at YTC, focused on: 1) how a variety of environmental variables influences knapweed distribution, 2) the use of Landsat Thematic Mapper (TM) imagery to map existing knapweed populations, and 3) the use of a logistic regression model and geographical information systems (GIS) to create a potential …
The Effect Of Salinity Level Upon The Yield, Root Growth, And Water Extraction Of Contrasting Rooting Subpopulations Of Alfalfa (Medicago Sativa) Under Conditions Of Zero Leaching, Laura A. Vincent
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A major problem in irrigated agriculture in the Western U.S. is the gradual accumulation of salinity in the plant root zone. These nonuniformly saline soils contain increasing amounts of salinity with depth, and salt accumulation is accelerated in situations where leaching is minimized. Root growth and thus plant yield is limited in these soils due to decreased water uptake. We studied the root growth of two subpopulations of alfalfa differing in their ability to produce fibrous roots to determine if altering root morphology would increase plant yield and water extraction, in an irrigated saline soil.
Soil profiles for a control …