K.V McCully1, M.J. Melanson1 and J. Dennis1
Abstract: A trial to evaluate various herbicides and rates for use in a commercial cranberry bog was conducted in Oromocto, NB. Casoron 4G applied at 50, 80, 110, and 140 kg/ha; Devrinol 50DF applied at 9, 13.4, and 20 kg/ha; Sinbar 80WP applied at 3.75 kg/ha; and a 33% mix of Roundup applied with a wiper were the treatments evaluated. Yield data, visual ratings on crop injury and weed control (Muhlenbergia uniflora; Calamagrostis canadensis - blue joint grass; overall weed control) were collected. Results indicated that all but the lowest Casoron rate (50 kg/ha) caused too much crop injury, and that 80 kg/ha was all that was required for effective weed control. The high crop injury was likely due to applications being later than desired, the high sand content (73%), and low organic matter (1.5) in the soil. Devrinol provided excellent crop tolerance but very poor weed control. Sinbar provided excellent weed control and crop tolerance, but reduced yields. Roundup applications were effective on the tall growing weeds. Crop injury resulted where low growing weeds were wiped. Yield data was variable and resulted in no significant differences between treatments. Treatments should be further evaluated.
1Potato & Horticulture Branch, NBDARD, Fredericton, NB E3B 5H1