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Sodium arsenite was once listed for controlling wigeongrass (Davison et al. 1962), but the many dangers involved with the use of this chemical soon rendered it obsolete. Stevenson and Confer (1978) reported control with atrazine at 1.0 ppm and postulated that similar control is achieved with 0.25-0.50 ppm. Wigeongrass greatly decreased within 6 weeks after receiving 2,4-D ester at 112 kg/ha, and only small numbers of plants were present 4 years after application (Getsinger et al. 1982). Correll et al. (1978a,b) suggested that alachlor and atrazine in runoff from agricultural fields lowers biomasses of wigeongrass and other submersed macrophytes in Chesapeake Bay. Concentrations of a large variety of herbicides in irrigation drainwater ponds supporting wigeongrass are listed in Schroeder et al. (1988).

References on biological control of wigeongrass are few. Aquarium tests of Duthu and Kilgen (1975) showed that white amur-common grass carp hybrids (Ctenopharyngodon idella X Cyprinus carpio) ate moderate amounts of wigeongrass. Buckingham (1982) raised at least one generation of the aquatic moth Parapoynx diminutalis on wigeongrass in quarantined indoor tests. This insect was being tested for control of nuisance hydrophytes. A recent literature search by Elakovich and Wooten (1987) showed that no known allelopathic plants affect wigeongrass and that wigeongrass produces no allelopathic effects on other plants.