Skip to Main Content

The Center for Native Grasslands Management

Title: Evaluation of pre-emergent herbicides for increasing establishment of native grasses on roadsides
Year: 2002
Author(s): Doak, S. O., Ervin, E., Hipkins, L.
Source Title: Proceedings of the Third Eastern Native Grass Symposium
Source Type: Proceedings
pages: 76
Original Publication:  
Abstract: The use of native plants in roadside situations is increasing. The slow establishment rate of many native grasses requires several years to provide ground cover adequate for erosion control and produce a permanent stand. This is especially true in roadside sites where poor soils and the removal of existing vegetation favor the growth of annual grassy weeds which can reduce or eliminate native plantings. The objective of this study was to evaluate several commercially available pre-emergent herbicides to determine their usefulness in reducing weed competition and increasing native grass establishment. The herbicide treatments were imazapic, quinclorac, dithiopyr, pendimethalin, oxadiazon, prodiamine, metsulfuron and an untreated control. The native grass species planted were buffalograss, blue grama, sideoats grama, little bluestem, big bluestem, indiangrass, and switchgrass. A site in Blacksburg, VA with a clayey B-horizon was used for this experiment. The initial treatments were applied on 16 May with seeding on 17 May 2000. Herbicides only, were applied in the second year on 17 April 2001. The control plots initially had the best percentage of germination but the native grasses were quickly reduced by the weed competition. Imazapic, oxadiazon and quinclorac all significantly reduced annual weed competition and helped establish most of the native grass species, although the best improvements were species specific. Pendimethalin, dithiopry and prodiamine had good weed control but generally hindered or prevented germination of most native grass species. Metsulfuron results were equal to the untreated plots. Blue grama plots treated with imazapic or oxadiazon all achieved over 70 percent cover, while indiangrass plots treated with imazapic or oxadiazon all achieved over 63 percent cover. The use of selected pre-emergent herbicides can greatly improve specific native grass establishment in sites where the vegetation has been removed.
Publisher: The North Carolina Botanical Garden, Chapel Hill, NC, October 1-3, 2002. Omnipress, Madison, WI
Editor(s): J. Randall