Published online by Cambridge University Press: 12 June 2017
Field experiments were conducted in 1974 and 1975 to evaluate the effect of seven herbicides applied preemergence and two herbicides applied postemergence on weed growth around 7-yr-old pecan [Carya illinoensis (Wang.) K. Koch ‘Elliott’ and ‘Desirable’] and 3-yr-old peach [Prunus persica (L.) Batsch ‘June Gold’] and to observe herbicidal tolerance as noted from visually expressed phytotoxicity. After 12 weeks, the best control of bermudagrass [Cynodon dactylon (L.) Pers.], purple nutsedge (Cyperus rotundus L.), and wild blackberry (Rubus cuneifolius Pursh) was obtained with glyphosate [N-(phosphonomethyl)glycine], napropamide [2-(α-naphthoxy)-N,N-diethylpropionamide] + glyphosate, and napropamide + terbacil (3-tert-butyl-5-chloro-6-methyluracil) + paraquat (1,1′dimethyl-4,4′-bipyridinium ion). The most effective overall control of yellow nutsedge (Cyperus esculentus L.), camphorweed [Heterotheca subaxillaris (Lam.) Britt. & Rusby], dogfennel [Eupatorium capillifolium (Lam.) Small], large crabgrass [Digitaria sanguinalis (L.) Scop.], and Florida pusley (Richardia scabra L.) resulted from napropamide + terbacil + paraquat. Herbicides used caused no visible toxicity to the immature pecan or peach trees.