K.V. McCully1, G. Chiasson2, E. Theriault3, M.J. Melanson1 and G.L. Graham1
Partner: New Brunswick Wild Bluberry Growers Association
Abstract: Two trials were established in the fall of 2004 to evaluate the control of bunchberry (Cornus canadensis L.) and crop injury with fall and spring applications of tribenuron methyl (Spartan) in a wild blueberry field post hand and mechanical harvest. Treatments of Spartan were applied at the label rate one week, two weeks, three weeks, four weeks and the following spring after harvest to the assigned blueberry plots. An untreated control plot was included for control and injury comparisons. Visual evaluations of crop injury and weed control were collected, along with crop yield parameters in the fall of the sprout year and crop yield at maturity. No difference in crop injury or weed control was noted between the harvest methods, where a fall Spartan application to control bunchberry proved to be successful. No significant difference was shown between the fall application timings. Decreased blueberry injury after a fall application was observed as compared to a spring application, especially within early season evaluations. Bunchberry control in the sprout year was improved in the fall applied Spartan treatments, with final control ratings between 90-100%, compared to the spring application with only 82% control within the hand harvest trial. A similar trend was observed within the mechanical harvest data. Furthermore, the fall application timing did not reduce any of the measured yield potential factors or have a significant effect on crop yield. The possibility of a fall application would help expand the application window for this herbicide, eliminating the restrictive nature of the current herbicide label. From these results, the use of Spartan post hand and mechanical harvest is recommended and could potentially be added to the product label as a new application timing which would be a benefit to commercial wild blueberry production. These experiments will be repeated in 2005 to verify the results found.
1 NB Department of Agriculture, and Aquaculture, Crop Development Branch, PO Box 6000, Fredericton, NB, E3B 5H1
2 NB Department of Agriculture and Aquaculture, Regional Agri-Business Development, 1425 King Avenue, Bathurst, NB, E2A 1S7
3NB Department of Agriculture and Aquaculture, Regional Agri-Business Development, P.O. Box 3058, Tracadie-Sheila, NB, E1X 1G5