Tuesday, November 6, 2007
170-9

Blue Grama (Bouteloua gracilis) Seedling Tolerance to Preemerge Herbicides.

Kevin Hensler1, James M. Goatley Jr.2, Shawn D. Askew3, John B. Willis3, and Erik H. Ervin2. (1) Virginia Tech, Virginia Tech, 424 Smyth Hall, Blacksburg, VA 24061, (2) Crop and Soil Environmental Sciences, Virginia Tech, 424 Smyth Hall, Blacksburg, VA 24061, (3) Plant Pathology, Physiology, and Weed Science, Virginia Tech, 203 PMB Glade Road Research Center, Blacksburg, VA 24061

Broadleaf and grassy weed pressure can create significant obstacles to establishment of desirable turfgrass species under low-maintenance conditions. Preemergence (PRE) herbicides can minimize these obstacles by reducing competition for resources and enhance initial establishment. Blue grama (Bouteloua gracilis) seedlings have shown tolerance to some PRE herbicides in preliminary trials. Application of these products at the time of seeding can enhance establishment success.

This study was conducted to evaluate population densities and dynamics between blue grama seedlings and an emerging weed community. A pot study will compare different PRE materials at planting depths of 0 and 10mm. Data analyzed will be: days to emergence; emergence percentage; plant height to monitor plant stunting and rate of mortality. A field study will be conducted to compare blue grama and weed populations during the establishment season. Herbicides evaluated are: atrazine; halosulfuron; imazapic; isoxaben; metolachlor; metsulfuron; oxadiazon; prodiamine; quinclorac.

Pot study and field application results will be presented.