A two-part study was initiated in 2008 and will continue through 2012. The first part of the study involved the selection of five commercial ‘Stevens’ bogs (with plans to add up to 5 more in 2009) to determine rate of cropping recovery following mowing. Mowed bogs were compared to unmowed companion beds under similar management. Bogs were mowed in the spring and biomass was evaluated in the fall. After 5-6 months, all mowed bogs had reduced biomass and reduced upright density per unit area compared to that on their unmowed companion bogs; this reduction was statistically significant at 2 of 5 (biomass) and 3 of 5 (upright density) sites. These sites will be followed for up to five years to determine rate of recovery. In the second part of the study, replicated trials were established on mowed or pruned vines (cv. Stevens) at the Rocky Pond Bog, Miles Standish State Forest. Three rates of Devrinol 50DF or Casoron 4G were applied to the vines after pruning or mowing treatment; untreated plots were also included in the study. Vines were evaluated three times after herbicide application and no vine injury was seen. In general, plots that received herbicides had reduced percent weed cover, with low to moderate rates of Devrinol and moderate to high rates of Casoron giving the best control. No significant treatment effect was noted in the pruned plots for any yield parameter (e.g., bbl/A, percent flowering uprights) or upright measurement. However there was a trend for higher yield in the plots that received Devrinol, perhaps related to the observed weed control.
This research was supported by funding from Cape Cod Cranberry Growers Association, Ocean Spray Cranberries, Inc., and Cranberry Research Foundation.