Executive Summary

The vegetation management project, based in the NSAC Weed Science Lab, spans from the initial selection of herbicides and herbicidal products that have the potential for use in blueberry fields, through the screening of those products, to the evaluation of products for potential minor use registration. It also encompasses the use of new technologies and the incorporation of this technology with existing management practices.

The demand for the proposed research has been established through support from industry and from Atlantic Canadian blueberry growers. Blueberry growers have expressed to the scientific community that weed control is an issue of high priority. There is recognition that an improvement in weed control programs will result in a reduction in cost and therefore an economic benefit.

The field trials have been designed to achieve results efficiently and to facilitate technology transfer to other groups in the scientific community such as the PMRA. The methodology chosen has been successful in producing clear and unbiased results in the past, and is a method accepted by the PMRA. Trials have also been designed to be incorporated in to a selected site with minimal impact on the surrounding environment.

Herbicide screening trials were initiated in the spring of 2004, in three different provinces in both pruning and fruiting season fields. The objectives were to determine the efficacy of herbicide application on weed control, and to determine crop tolerance. Further objectives included an investigation of several products for use in organic blueberry production. Initial results indicated that product 2 and product 5 consistently resulted in unacceptable crop damage. However these products also produced fairly effective results against several ubiquitous weed species. This highlights the possibility of developing alternative use patterns for these products in order to avoid the unwanted crop damage. In addition, product 10 (a reduced risk product) did not demonstrate crop damage in either the pruning or fruiting season, and did effectively control some target weed species. Due to the interest developed surrounding this product, research directions for the coming season will include progressive research steps such as dose response and timing trials. These trials will accelerate the registration process if the industry supports this objective. Organic products investigated showed some effectiveness against certain weed species however weeds did often recover from the initial damages.

The initial results of this research effort are preliminary. Several seasons are required to conclusively eliminate or include certain products in the more advanced stages of product development such as timing or dose response trails. This first season was successful with only minor problems such as climatic effects on herbicide efficacy. The data from this season will be combined with the data from the following field season to form conclusive results which can then be broadly disseminated to the parties of interest.

Partners: The New Brunswick Wild Blueberry Growers Association, the Wild Blueberry Producers’ Association of Nova Scotia, the Prince Edward Island Wild Blueberry Growers’ Association and Oxford Frozen Foods /