A Survey of Weeds in Various Crops in Georgia¹

Abstract

A survey of county extension agents was conducted in 1998 to determine the most troublesome weeds in corn, cotton, forages and pastures, peanut, small grains, soybean, tobacco, and vegetables in Georgia. The most troublesome weed statewide averaged over all crops was sicklepod. It was the most troublesome weed in cotton and soybean and among the four most troublesome weeds in corn, peanut, tobacco, and vegetables. Sicklepod was found in each of the nine climatological districts and in all the crops surveyed. Perennial nutsedge species were the second most troublesome weeds in Georgia. They ranked as the most troublesome weeds in tobacco and vegetables and were among the top five most troublesome weeds in corn, cotton, peanut, and soybean. Pigweed species were ranked third averaged over all the crops surveyed and were the second most troublesome weeds in cotton and vegetables and among the top five most troublesome species in corn, soybean, and tobacco. Morningglory species were listed as troublesome in six of the eight crops surveyed and ranked fourth overall. Similarly, Texas panicum was found in all districts and was the fifth most troublesome weed species. Texas panicum was the most troublesome weed in corn and among the top five most troublesome weeds in peanut, soybean, and tobacco. Florida beggarweed was the most troublesome weed in peanut, the second most troublesome weed in tobacco, and a top-10 weed species in corn, cotton, soybean, and vegetables, resulting in a ranking of sixth overall. Wild radish, large crabgrass, and tropic croton were the seventh through the ninth most troublesome weeds. Wild radish was the most troublesome weed of small grains and the sixth most troublesome weed of vegetables. Large crabgrass was the second most troublesome weed of forages and pastures and was reported in six other crops. Tropic croton was a troublesome weed in seven of the eight crops surveyed and was among the top five most troublesome weeds of cotton and peanut. The 10th most troublesome weed overall was bahiagrass, the most troublesome weed of forages and pastures.

Adaptive Differentiation of Quantitative Traits in the Globally Distributed Weed, Wild Radish (Raphanus raphanistrum)

“…Thought to be native to the Mediterranean basin (Hulten and Fries 1986;Holm et al 1997), wild radish has successfully colonized a variety of locations, leading to its naturalization on all continents except Antarctica (Holm et al 1997). Not only has wild radish colonized these new areas, but also it has become a major agricultural weed, causing yield losses in a variety of crops in North America (Webster and MacDonald 2001;Warwick and Francis 2005), Europe (Bostrom et al 2003), and Australia (Streibig et al 1989;Cousens et al 2001). Due to the self-incompatibility system of wild radish (Sampson 1964) and its lack of vegetative reproduction, this species relies completely on pollination by insects for reproduction.…”

The biology of Canadian weeds. 132. Raphanus raphanistrum L.

“…In the southeastern United States, R. raphanistrum is reported as the most troublesome weed in small grains (Elmore 1986, cited in Schroeder 1989Webster and MacDonald 2000). The species is primarily a winter annual in southern US regions, with most germination during fall and winter months and limited germination year round.…”

“…It has also been reported in corn (Zea mays L.) and strawberry crops in Quebec (Doyon and Bouchard 1981;Doyon et al 1982;Lemieux et al 1988c). In Georgia (USA), it is the sixth most troublesome weed in vegetable crops (Webster and MacDonald 2000).…”

Mulches for Weed Management Mulches for Weed Management

“…These are two of the most problematic weeds for vegetable production in the Southern U.S. (Webster and MacDonald, 2001). Unlike most weeds, both yellow and purple nutsedge have the ability to pierce plastic mulches (Figure 2) and successfully compete with crops (William, 1976;William and Warren, 1975).…”