Using cover crops and crop diversity to optimize ecologically based weed management

Using cover crops and crop diversity to optimize ecologically based weed management

Summary

This project builds on activities being conducted as part of a USDA Transition to Organic (Transition) funded grant and a Northeast Region Integrated Pest Management (NEIPM) Research and Extension grant. A component of both the Transition and NEIPM studies involves the characterization of soil surface dwelling arthropod populations and how these populations may be impacted by various cultural weed management strategies such as cover cropping and crop rotation as well as by mechanical weed control methods. This NESARE grant is building on this work by expanding our research efforts at understanding the impact of cropping system diversity and disturbance on weed seed predation by beetles. The education project is focusing more broadly on demonstrating how cover crops and increased crop diversity promote ecologically-based weed management (EBWM). On-farm demonstrations and field days are focusing on cover crop management, cropping sequence, tillage, and other cultural management impacts on weed management. We are conducting university-based and on-farm research and demonstrations that examine the relationship between cultural practices, abundance and activity of weed seed predators, weed populations and crop yield in sustainable crop production systems. Farmers, extension agents and other agricultural professionals are attending field days and learn first-hand about the opportunities and benefits for EBWM strategies.

Objectives/Performance Targets

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.

Accomplishments/Milestones

•Twenty-five county agents and other agricultural professionals along with some key farmers will help identify and select eight farms to participate with the farm-based research and field day activities.

County extension educators and select farmers were contacted in 2005 and asked for input in identifying potential farmer participants. From this list, three farms in Pennsylvania and three farms in Maine were identified and contacted to participate. This included a university research/education facility in each state.

•Six farmers will cooperate with the project team to create on-farm research and demonstrations in Pennsylvania and Maine. Selected farmers will respond to interviews providing detailed crop management information.

Selected farmers helped set up and demonstrate the utility of cover crops on their farms. Data on their farm operation including goals and limitations were collected and used in deciding appropriate demonstrations.

•The research and education planning team will initiate the weed seed predation research project at the university research farm and at the selected farms.

In 2005 and 2006, some seed predation monitoring studies were set up on demonstration farms. The primary purpose in these studies was to characterize potential seed predators in producers fields. In addition, in 2007 a field experiment was completed in Pennsylvania that examined the potential synchrony of giant foxtail and H. pennsylvanicus, a know seed predator in the Northeast. The results showed that foxtail emerging from mid May until mid June flowered and set seed at the same time. Peak seed rain was later in 2006 than 2005. Differences in mid and late summer rainfall (2006 was wetter) may have contributed to this difference between years. The convergence in phenological development across planting dates observed in this experiment supports the concept that the later the foxtail seedling emerges, the faster the plant will develop and that flowering and pollination are directly related to the shortening of daylength. H. pensylvanicus activity-density did not synchronize completely with giant foxtail seedrain; peak activity density occurred in August, while peak foxtail seedrain did not take place until October. Other research has suggested large crabgrass (Digitaria sanguinalis) and fall panicum (Panicum dichotomiflorum) may be better candidates as well as yellow foxtail (S. glauca). These findings suggest that giant foxtail seed may not be a key food source for the survival of H. pensylvanicus in the Northeast, especially in tilled cropping systems. However, H. pensylvanicus may prefer and may have synchronized with other annual weed lifecycles.

•Five hundred farmers and 100 extension and secondary education professionals and 200 other agricultural professionals and will attend one or more field days and learn concepts and techniques for EBWM.

In addition to the activities reported in last year’s report, in 2007, a cover crop summit was held at the Penn State Rock Springs Research Farm. About 90 people attended the field day and 52 evaluations were returned. Of those in attendance, 44 were male and 10 were female, 35 were full or part-time farmers, 13 were educators, 12 were governmental agency employees, 8 were goods or service providers, 6 were members of environmental organizations or advocates, 2 were researchers and 1 was a student. Of the farmers, 18 were from conventional operations and 15 were using organic practices in some manner. The four key topics discussed included 1.) cover crop selection, 2.) life in the soil, 3.) cover crop and weed management, C:N dynamics and legume N contributions. Of the 45 individuals responding to the question of “how likely are you to make a change in your farming practice as a result of attending todayprogram”, 44 claimed somewhat to very likely. When asked if the event inspired them to get more information during the next on the cover crop topics, 43 of 52 individuals claimed moderate to considerable inspiration to get more information. Comments and suggestions for the summit included “good conference, great work, good presentations, nice format- keep it up, very informative and helpful”

•One hundred farmers and ag professionals will respond to evaluative surveys that determines how actively they have adopted or promoted EBWM.

Evaluations were conducted and participants responded very positively about the educational activities (see Outcomes). In addition, Maine hosted the Northeast SARE PDP/AC summer tour/meeting in 2006. Two of the farm visits on the stop are participating in this project. One stop included a presentation and demonstration of the weed predator test kits and a brief presentation by Bill Curran and Rick Kersbergen. The SARE group also visited Peacemeal farm, also a cooperator on the project.

•A focus group of extension educators will be chosen to provide more detailed information about program assessment and ideas.
•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.

The milestones above are still in progress. Additional field day activities will take place in 2008 and will continue to focus on EBWM trying to document impacts and outcomes.

Impacts and Contributions/Outcomes

A number of successful field day activities were conducted over the last three years. Participants were evaluated at these events to gauge success of the events. A portion of the evaluation asked individuals to gauge their understanding of several concepts before and after attending the educational program. A summary document is under preparation and will be included in the final report and in extension program impact reports and in other appropriate venues. Several extension publications have been developed and more are in the works.

Publications to date

Mortensen, D., W. Curran, M. Ryan, A. Hulting, and S. Mirsky. 2006. Weed germination periodicity: When do weeds wake up? Dept. Crop & Soil Sciences, College of Agricultural Sciences, University Park, PA 16802.

Galladt, E. and R. Kersbergen. 2006. Ecologically-based weed management – strategies for managing weeds without herbicides. College of Natural Sciences, Forestry, and Agriculture, University of Maine, Orono.

Curran, W.S, A.G. Hulting, R.J. Hoover, M. E. Barbercheck, C. Reberg-Horton, and E. R. Gallandt. Ecologically Based Weed Management Principles: Integrating Research and Education. Abstr. WSSA, San Antonio, TX, February, 2007.

Curran, W.S. and M.M. Ward. Is Harpalus pensylvanicus activity density synchronized with giant foxtail? Abstr. WSSA, Chicago, IL, February, 2008.

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