In reading the responses to my original posting on the impacts of Vision herbicide on wild blueberry species it appears that there is some confusion as to whether our research was conducted in forests or commercial blueberry fields. To clarify, we followed berry production and vegetative recovery of two species of Vaccinium (lowbush and velvet leaf blueberry) for three growing seasons following operational silvicultural use of Vision herbicide (commercial formulation containing glyphosate, 356 g/L present as isopropylamine salt) in a young jack pine plantation in northwestern Ontario. Vision herbicide was prescribed in order to release planted jack pine seedlings from trembling aspen, green alder, pin cherry, beaked hazel and willow. Compared to the untreated control areas, operational Vision reduced total fruit production by Vaccinium spp. significantly. A longer study conducted by Freedman et al. (1993) found that blueberry cover failed to return to pre-treatment levels even 6 years after Vision spraying. In talking to many industrial foresters I have often been told that blueberry health shouldn't even be a concern in forests managed for timber production. I totally disagree with this statement. To ignore the social, aesthetic, ecological and economic contribution of non-timber species in managed forests is silly. Production of berries by blueberry and other fruit producing species is important to berry pickers and are of essential browse value to bears and other wildlife. The traditional use of such plants contributes to the income of aboriginal and non-aboriginal communities in rural Canada and througout the boreal forest regions of the world. Not to mention, these plants contribute to soil stability following clearcutting, due to their dense network of roots and rhizomes (Vander Kloet and Hill 1981, Haeussler et al. 1990). Herbicide application for vegetation managment purposes not only reduces fruit yield by many understory species but also contaminates fruit for some time. A paper by Roy et. al (1989) published in the Canadian Journal of Forest Research documents this fact. Their research found that residues of glyphosate on blueberry and raspberry fruit, remained above the maximum permissible residue level (0.01 ppm) as established by the Health and Welfare Canada, Food and Drug Regulation (1980) for 60 and 30 days, respectively. In Ontario, Canada, there exists legislation (the Crown Forest Sustainability Act 1994) that is suppossed to ensure that forestry practices are consistent with the goal of protecting biodiversity and managing for the sustainability of less economically important "forest values". The evidence that we have gathered in our own research and that i have read elsewhere convinces me that forest herbicide use is not consistent with the goals of sustainable forestry. cheers Faizal Moola Phd. Applicant Biology, Dalhousie University [Settings] LastSettingsCategory=0
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