Field, greenhouse, and laboratory studies were conducted to evaluate the feasibility for the use of native warm season grasses (NWSGs) on North Carolina roadsides. Location, equipment, and multiple grass species were assessed to determine the ideal method and timing as well as specific herbicide regimes.
Few differences were present between planting equipment used, but planting date was extremely important. Stand establishment was very sensitive to environmental conditions and establishment often took two or more years. Thus, individual construction projects should be critically evaluated for NWSG planting depending upon whether ideal establishment conditions will be present.
Studies were also initiated to assess the best means of control for alligatorweed and Japanese knotweed, two invasive and problematic species among North Carolina roadsides and right-of-ways.
At 7 MAT, Japanese knotweed control with glyphosate, imazapyr, glyphosate plus imazamox, and glyphosate plus imazapyr was at least 93%. Glyposate plus penoxsulam controlled the plant 75%. Treatments that did not include imazapyr or glyphosate did not exceed 20% control.
Imazapyr provided excellent control of alligatorweed in almost every trial conducted. No other active ingredient evaluated was as consistent as imazapyr.
