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Filtering by: Subject No-tillage -- Oregon, Eastern Remove constraint Subject: No-tillage -- Oregon, Eastern Committee Member Pyke, David Remove constraint Committee Member: Pyke, David

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  • Seed bank response to juniper expansion in the semi-arid lands of Oregon, USA

    Creator:
    Duncan, Corinne M.
    Abstract:
    Expansion of Juniperus occidentalis into the sagebrush steppe has resulted in significant changes in understory composition. A consequence of increased J. occidentalis dominance may be a depletion of the seed bank. The potential for depletion is problematic because a reduction in the amount of species available from the seed bank...
    Resource Type:
    Masters Thesis
    Full Text:
    thresholds based on seed density. Two eastern Oregon sagebrush steppe sites where chosen to represent the

  • The Biology and ecology of weeping alkaligrass (Puccinellia distans) and Nuttall’s alkaligrass (Puccinellia nuttalliana)

    Creator:
    Tarasoff, Catherine
    Abstract:
    Weeping alkaligrass (Puccinellia distans) and Nuttall’s alkaligrass (Puccinellia nuttalliana) infest Kentucky bluegrass seed fields of eastern Oregon. Weeping alkaligrass is an introduced species from Eurasia, whereas Nuttall’s alkaligrass is native to semi arid environments of western North America. These species are often referred to collectively as ‘alkaligrass’; however, for farmers...
    Resource Type:
    Dissertation
    Full Text:
    Nuttall’s alkaligrass (Puccinellia nuttalliana) infest Kentucky bluegrass seed fields of eastern Oregon

  • Quantification of vegetation diversity and variation on intact and degraded rangelands

    Creator:
    Dysart, Patricia L.
    Abstract:
    Vegetation diversity in the Wyoming big sagebrush/Thurber needlegrass (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young/Achnatherum thurberianum (Piper) Barkworth. syn. Stipa thurberiana Piper) plant association was studied across a condition class gradient in southeastern Oregon. All observable vascular plant species were counted during 6 seasons and 2 years and diversity...
    Resource Type:
    Dissertation
    Full Text:
    (continued) Fi2ure Pa2e 4.5 Patterned soil in the sagebrush steppe of eastern Oregon(photo