Released July 2, 2009
SEARCY, Ark. - Good cultural practices account for 60 percent to 70 percent of turfgrass weed control, said Sherri Sanders, White County extension agent for the University of Arkansas Division of Agriculture.
Maintaining a dense, vigorous lawn is essential to weed prevention. Herbicides should be considered a supplement, not a stand-alone weed control practice.
"If herbicide use is not accompanied by proper cultural practices, the weed problem will return because the deficiency, which led to the weed invasion, has not been corrected," she said. "When herbicides alone are used, the symptoms and not the cause, of a weedy lawn are being treated."
Weeds can indicate specific problems. Soil compaction may lead to encroachment of species like annual bluegrass and goosegrass. Poor drainage favors invasion by sedges, rushes, and Virginia buttonweed. Saturated soil stresses the turfgrass by blocking oxygen from the roots. The presence of legumes such as white clover and lespedeza is often an indication of low nitrogen level. Cultural and environmental problems should be corrected before embarking on a program of herbicide use.
Sanders recommends Water deeply and infrequently. Light, frequent irrigation encourages shallow rooting. Early morning is a good time to water because evaporation loss is minimal, the wind is usually calm, and early watering allows the grass foliage to dry during the day.
Patch bare areas as soon as possible to prevent invasion by weeds. Grasses such as Bermuda and St. Augustine will readily fill in bare spots if a few plugs or sprigs of healthy grass are planted in these areas. Re-seeding is an option with common bermudagrass and tall fescue. Slow growing grasses such as zoysia and centipede may be sprigged or plugged, but it is much faster to sod the bare areas.
Soil test and add lime, if necessary, to bring pH within soil test recommendations. Fertilize according to soil test recommendations to encourage vigorous turf. The University of Arkansas Division of Agriculture provides soil testing at no charge to the homeowner. Simply bring a sample of dry soil from several spots in your yard to your county Extension office. Results usually are back within two to three weeks.
Mechanical control methods such as digging and pulling can be useful when dealing with small numbers of weeds. Hand-pull or dig new or exotic weeds to prevent their spread. Mowing is another method of mechanical weed control.
For additional information, contact your county office of the University of Arkansas Cooperative Extension Service or visit the website at http://www.uaex.edu/. Two suggested publications are "Choosing Grass for Arkansas Lawns," http://www.uaex.edu/Other_Areas/publications/PDF/FSA-2112.pdf, and "Fertilizing your Lawn," at http://www.uaex.edu/Other_Areas/publications/PDF/FSA-2114.pdf
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http://www.uaex.edu/news/july2009/0702lawn_weeds.htm
Editor: Elizabeth Fortune, (501) 671-2120, efortune@uaex.edu
