Two sheep for 30 days plus flea beetles had one-fourth the leafy spurge cover compared to where flea beetles alone were present. Two sheep for 30 days plus flea beetles had less than one-third the leafy spurge cover compared to 2 sheep for 30 days without flea beetles. Kentucky bluegrass cover decreased to zero at all stocking rates and grazing durations where flea beetles were not present. These increases were in response to the decreases in leafy spurge cover from these same treatments. Kentucky bluegrass cover increased as grazing duration increased for these treatments.
Kentucky bluegrass cover to zero.
At 3 locations, prairie junegrass was the most sensitive to in situ Russian knapweed allelochemicals. 1999 Russian knapweed expansion was evaluated using a model to simulate shortgrass vegetation in Colorado. Results showed a strong species-specific response to Russian knapweed allelopathy. Data indicate that prairie junegrass would be a poor choice to renovate Russian knapweed infested land because of its sensitivity to Russian knapweed allelopathy while western wheatgrass would be a good choice. The model was used to isolate the relationship of soil texture and allelopathic effects.