Weed control strategies for rice (Oryza sativa L.) and soybean [Glycine max (L.) Merr.] emphasize integration of cultural and chemical practices (16, 30, 31). Numerous herbicides are registered and used as preplant, preemergence, or post-emergence applications for control of weeds in rice and soybean (3, 16, 25). Although these herbicide treatments control most of the problem weeds in rice and soybean, most fail to control northern jointvetch [Aeschynomene virginica (L.) B.S.P. # AESVI] in either crop. The two most effective herbicides, 2,4,5-T [2-(2,4,5-trichlorophenoxy) acetic acid] and silvex [2-(2,4,5-trichlorophenoxy) propanoic acid], for control of northern jointvetch in rice have been under the U.S. Environmental Protection Agency's (EPA) Rebuttal Presumption Against Registration (RPAR) process which may ultimately cancel the use of both herbicides in rice (50). New, effective control strategies are needed for control of northern jointvetch in rice and soybean.