Control of Persimmon with Various Herbicides and Methods of Application

Abstract

We compared various rates of 2,3,6-trichlorobenzoic acid (2,3,6-TBA), 3,6-dichloro-o-anisic acid (dicamba), and 4-amino-3,5,6-trichloropicolinic acid (picloram), and various methods of application on persimmon (Diospyros virginiana L.). Single rates of 2,3,6-trichlorophenylacetic acid (fenac) and (2,4,5-trichlorophenoxy)acetic acid (2,4,5-T) also were included. In one experiment, 8 lb/A of dicamba injected into the soil killed significantly more persimmon than the same rate applied to the soil in 4-inch bands. Otherwise, with given herbicides at comparable rates, defoliation and mortality of persimmon were similar with all methods of soil application. Foliage applications of dicamba or picloram at relatively low rates caused defoliation and mortality of persimmon equal to soil applications of dicamba or picloram at high rates. Dicamba was more effective than equal rates of 2,3,6-TBA for killing persimmon. Picloram at 2 lb/A and dicamba at 4 lb/A, as foliage applications, defoliated and killed persimmon to nearly the same extent. Fenac was relatively ineffective for killing persimmon. Soil treatments with picloram and dicamba killed 22 to 30% more persimmon when applied in summer than when applied in spring. Spring and summer foliage applications of dicamba and 2,3,6-TBA caused similar defoliation and mortality of persimmon, but mortality of persimmon was somewhat higher with spring than with summer foliage applications of picloram. Summer basal treatment with 2,4,5-T killed more persimmon than spring basal treatment.