Post-emergence herbicide for food crops; also effective vs mildew. Prepn of salts: B. Walworth, E. Klingsberg, DE 2260485; eidem, US 3882142 (1973, 1975 both to Am. Cyanamid); B. Cross et al., J. Heterocycl. Chem. 17, 905 (1980). Physical properties and herbicidal activity: N. E. Shafer, Proc. 12th Br. Weed Control Conf. 1974, 831. Effect vs mildew: R. J. Winfield et al., Proc. Br. Crop Prot. Conf. - Pests Dis. 1977, 57. HPLC determn in commercial formulations: C. Barry, R. K. Pike, J. Assoc. Off. Anal. Chem. 63, 64 (1980); in water: M. C. Carneiro et al., J. Chromatogr. A 669, 217 (1994).