Cultural Management of Weeds in Turfgrass

Abstract

Cultural management of weeds in turfgrass is the use of mowing, fertilization, irrigation, cultivation, planting, and turfgrass selection to affect weed populations. There is consensus in the literature on a few cultural factors influencing some weeds in cool‐season turfgrasses. Taller mowing height, 4 to 8 cm, depending on turfgrass, reduces populations of crabgrasses (Digitaria spp.) in Kentucky bluegrass (Poa pratensis L.) and fescues (Festuca spp.). A high rate of N fertilization (100–300 kg N ha−1 yr−1) reduces populations of crabgrasses, dandelion (Taraxacum officinale G.H. Weber ex Wiggers), and other broadleaf weeds in cool‐season turfgrasses. Annual bluegrass (Poa annua L.) may be favored by this high rate of fertilization. Fertilization of turfgrasses when they are not actively growing increases weeds. Slow‐growing grasses such as zoysiagrasses (Zoysia spp.) have more weeds at high N fertilization rate. Environmental stresses including drought injury, unnecessary aeration or vertical mowing, biotic stress such as nematode and insect herbivory, and diseases contribute to weed colonization. Adapted cultivars and species of turfgrasses that are genetically resistant to biotic and environmental stresses have the fewest weed problems. Adapted turfgrasses can sometimes be effectively managed in the absence of herbicides, especially if they are well established. The generalized mechanisms for cultural management of weeds are poorly understood. Research is needed on optimizing the choices of herbicide and/or cultural practices as part of an integrated management system for turfgrass.

Impact of mowing and weed control on broadleaf weed population dynamics in turf

“…This would be the result of the reduced competitive pressure from the dominant species (dandelion) on other broadleaf weeds. Turfgrass survives and predominates in ecosystems with periodic defoliation by fire, grazing, or mowing, but mowing below the tolerance level may be harmful to a turfgrass species and give weeds competitive advantage (Busey 2003). In this study, mowing alone at any level did not improve turf quality at either sites in the two years (Table V), which indicates that turf quality was more determined by level of weed infestation rather than regular mowing.…”

“…Close mowing favours short ecotypes or plant species which have the potential to grow in a rosette habit like broadleaf plantain (Warwick & Briggs 1979). Low mowing heights are always associated with more weeds and may change the species composition, abundance, and diversity (Busey 2003). This may explain the trend of increasing colonization of several species at the 3 Á5 cm compared with higher mowing heights (Table II).…”

“…The exact tolerated mowing height for a specific turfgrass is difficult to predict because it is a result of interactions between turfgrass genotype, climate, cultural practices, time of the year, and other environmental influences (Turgeon 1985, Fry & Huang 2004. As a consequence of mowing, population abundance and diversity of weeds may change, creating new competitive environments amongst existing weed species and between the crop (turfgrass) and the weeds (Busey 2003). Practices that favour crop growth will generally disfavour weed abundance (Radosevich et al 1997).…”

“…Practices that favour crop growth will generally disfavour weed abundance (Radosevich et al 1997). Cultural management practices have been used to control weeds in turfgrass for some time (Hanson 1921: cited in Busey 2003 and greater reliance on cultural management to control turfgrass weeds may reduce dependence on synthetic herbicides (Busey 2003).…”

Phytosociological Survey of Weeds in Carpet Grass in Distinct Periods of the Year

“…Carpet grass or curitibana (Axonopus compressus is widely used to form lawn in gardens, parks, residential areas, public squares, among others, in Southern Brazil (Lorenzi and Souza, 2001;Busey, 2003). Species A. compressus has good tolerance to colder weather and little resistance to drought.…”