Last updated on 01/22/2018
Smith RG, Birthisel SK, Bosworth SC, et al. Environmental correlates with germinable weed seed banks on organic farms across northern New England . Weed Science. 2018;66 (1) :78-93.
The northern New England region includes the states of Vermont, New Hampshire, and Maine and encompasses a large degree of climate and edaphic variation across a relatively small spatial area, making it ideal for studying climate change impacts on agricultural weed communities. We sampled weed seed banks and measured soil physical and chemical characteristics on 77 organic farms across the region and analyzed the relationships between weed community parameters and select geographic, climatic, and edaphic variables using multivariate procedures. Temperature-related variables (latitude, longitude, mean maximum and minimum temperature) were the strongest and most consistent correlates with weed seed bank composition. Edaphic variables were, for the most part, relatively weaker and inconsistent correlates with weed seed banks. Our analyses also indicate that a number of agriculturally important weed species are associated with specific USDA plant hardiness zones, implying that future changes in climate factors that result in geographic shifts in these zone will likely be accompanied by changes in the composition of weed communities and therefore new management challenges for farmers.