Invasive plants have the capacity to transform landscapes and alter ecosystem function, causing significant economic and ecological damage. These effects include displacement and reduction of native flora and fauna, altered fire regimes, modification of biotic and abiotic soil properties, as well as local, regional, and global economic impacts. With such...
The effect of soil water suction and soil temperature on rates
of transpiration, photosynthesis, respiration and nitrogen fixation of
soybean (Glycine max. Merrill, var. Chippewa 64) seedlings was
studied. A special apparatus was developed in which the soil water
suction of several cells with soybeans growing in them could be...
Vegetation as a soil-forming factor was studied under forest
transition and grass while attempting to keep other soil forming factors
constant in the western part of the Willamette Valley, Oregon. The
physiographic units consist chiefly of the interior foothills and slopes
formed from an old basaltic flow with some interspersed...
This study was undertaken to determine both the amount and the
spatial variability of sand, silt, clay, and six fractions of coarse
fragments in soils representing harsh sites for reforestation. Particle size data were collected because of their direct relationship to
water holding capacity and the plantability and survivability of...
This research assessed certain specific plant-soil and community
interrelationships in eastern Oregon habitat types dominated by
subspecies of Artemisia tridentata.
The first evaluation described plant-induced soil chemical patterns for Artemisia tridentata plant communities of high perennial
grass-low shrub and low perennial grass-high shrub composition. Soil
concentrations of total nitrogen, organic...
Infiltration, soil erosion, nitrogen loss and soil profile
characteristics were measured on 36 sites representing land occupied
by Artemisia tridentata ssp. tridentate, wyomingensis, and vaseyana.
Infiltration, soil erosion, and nitrogen loss were strongly correlated
but highly variable. Soil loss, but not infiltration or nitrogen
loss was significantly different between subspecies....
Agronomic and microbiological studies were conducted on "Anchor" alfalfa (Medicago sativa L.) established from uninoculated seed on three Aridisols in central Oregon. Significant responses to 230 Kg N per ha (NH₄NO₃), which was applied in mid-April and after each first and second harvests, were observed in yield parameters of the...