This project included two primary objectives. First, we conducted educational programs focused on cover crops and ecologically-based weed management that included field demonstrations. Second, we conducted research at university research farms and in producer’s fields to assess the presence of potential weed seed predators. A total of 12 field days were conducted in Maine and Pennsylvania directly reaching about 700 individuals. In the follow-up project survey conducted in fall of 2008, respondents reported that after attending one or more activities offered in this project, 3% had transitioned to organic production and 19% were more interested in transitioning to organic production, 47% were thinking about how cover crops and crop rotation fit into organic production, 41% were using cover crops for weed suppression and 62% of the individuals were looking much harder at using cover crops for weed suppression, 21% were interested in cover crop roller design and use, 40% were considering the effects of tillage and mowing for weed suppression, 15% were considering how to better use seed predators to suppress weeds, 31% had reduced pesticide use, 36% planted cover crops to supplement cash crop fertility, 55% used cover crops to improve the soil, 31% used cover crops to conserve beneficial organisms and 48% were thinking more about beneficial soil organisms, 33% used a new cover crop species or mixture and 62% were interested in discovering and learning about new cover crop species, about 40% had reduced the amount of tillage they used as well as reducing fuel use, and 31% were trying no-till and 50% were interested in learning more about no-till equipment. A total of 52% had adopted or promoted more sustainable ag practices on their farm or in their work. Finally, 88% of the respondents felt the changes they had made in the last 3 years improved the environment, 57% said it made them more profitable, and 36% thought it provided greater social benefit to their operation or in their work (see Appendices for complete survey results).
The seed predation research focused on two potentially key carabid beetles that are known weed seed predators. Both are commonly found either in Pennsylvania or Maine and both were more prominent towards the middle and end of summer. In Pennsylvania, the activity density (abundance) work suggested that cropping systems with little or no late summer tillage or mowing encourage H. pensylvanicus populations. In Maine, this research suggested that while the presence of vegetation alone encourages adult H. rufipes populations, some level of soil disturbance was needed to achieve even higher densities of the beetles. Although the activity density experiments focused on these two carabids, the seed predation work showed that numerous organisms likely feed on weed seeds. Seed predation experiments conducted in Pennsylvania showed giant foxtail seed removal (feeding) rates between 40 and 90% over a 14-day period. We observed at least 60% giant foxtail removal throughout the summer in three of five sampling periods. Distinct early and late summer peaks did not occur in our research further suggesting that several seed predators likely contributed to seed losses observed. Observations during this experiment suggest that higher frequencies of tillage could decrease the level of H. pensylvanicus activity density in certain crops. However, carabid beetles may not prefer one cropping system throughout the entire growing season but may tolerate a specific crop type during a specific time in the season. At Penn State, most of the predation was caused by insects and seeds were consumed during the entire summer. At Cedar Meadow Farm in Southeast Pennsylvania, vertebrates (mice and other rodents) probably played a larger role, although insect predation was also detected. These experiments clearly showed that a number of organisms consume weed seeds and that it can occur in different cropping systems and during most periods of time during the summer. Both the presence of plant cover and reduced tillage at key periods of time and especially later in summer should help conserve and promote weed seed predators in northeast cropping systems.
Of the 500 farmers attending a field day, 25 will adopt some aspect of ecologically based weed Management (EBWM) identified through this research. Of the 100 extension and other agricultural professionals attending field days, 50 extension and other education professionals will incorporate knowledge into their educational programming, and 15 will work with farmers or farm youth to actively promote EBWM.
This performance target was mostly achieved, although we did not accomplish documenting some of these very specific targets and especially the final target of 15 education professionals working on EBWM’s with farmers. We believe this is happening on the ground, but have not documented this goal.