1. Agridex, Helena Chemical Corp., Memphis, TN.
2. Letters following this symbol are a WSSA-approved computer code from Composite List of Weeds, Weed Sci. 32, Suppl. 2. Available from WSSA, 309 West Clark Street, Champaign, IL 61820.
3. Fehr W. R. and Caviness C. E. 1977. Stages of soybean development. Iowa Agric. Exp. Stn. Spec. Rep. 80.