Roundup and Staple have several complementary, off-setting strengths and weaknesses. Roundup has good activity on perennials, grasses and cocklebur and has a potentially low cost; however, it has no residual activity and can be weak on morningglory and velvetleaf. Staple has relatively good morningglory and velvetleaf activity and residual control. However, Staple provides inadequate grass control, may not control larger cocklebur and is relatively expensive. A Roundup-Staple tank mixture would appear to be advantageous; however, tank mixtures of other herbicides often interact and result in reduced weed control or unacceptable crop injury.