Organic producers generally rely heavily on tillage for weed control. In contrast conventional producers can utilize no-tillage techniques but must rely on herbicide burn down before no-till drilling crops. Researchers from the Rodale Institute in Kutztown, PA have developed an organic no-tillage technique that allows organic growers to benefit from the soil building characteristics of no-till without reliance on chemical weed control. Their organic no-till system relies on thickly planted winter covers which when rolled down create a dense mulch of organic material. Field crops are no-till planted into this mulch which suppresses weeds until the crop canopy closes providing additional weed suppression. However, few on farm trials of the roll down technique have been successful due to a variety of weather, pest and farmer oversight related problems. Some trials have been conducted in other regions where differing climatic conditions required use of cover crops not appropriate for this region. Here we propose to test the organic roll down technique in comparison to a control where cover crops are disked into the soil surface. This will allow the collaborating grower to compare yield and weed suppression between the organic no-tillage method and his general best management practices. The results of this trial will be shared with other growers through two farmer field days and articles in the Penn State University “Small Fruit and Vegetable Gazette”. Tilled- annual agriculture, covering over three quarters of global agricultural area , has severely impacted soil fertility, water quality, biodiversity and ecosystem function [2-5]. Currently, twenty per cent of croplands are degraded . No-tillage and conservation tillage systems are increasingly seen as a solution to soil degradation, increasing soil carbon and decreasing soil erosion . However, no-tillage systems rely on herbicide burn down before crop establishment. These herbicides are generally regarded as benign compared to insecticides, but they remain the largest agricultural pesticide class, accounting for 60 percent of the total amount of pesticide used in 2001 . Intensive herbicide use has been associated with a variety of human health risks, negative impacts on wildlife and the development of herbicide-resistant weeds. Organic agriculture eliminates the use of synthetic chemical inputs, while increasing soil organic matter and nitrogen, lowering fossil energy inputs, and conserving soil moisture and water resources , but it relies heavily on cultivation in order to control weeds. In order to increase the overall sustainability of agriculture in the region it is important to consider techniques that have the soil conservation benefits of no-till and decreased chemical usage of organic systems. Researchers at the Rodale Institute in Kutztown, PA have developed a technique that does just that. Their organic no-till systems rely on thickly planted winter covers which when rolled down create a thick mulch of organic material. Field crops are no-till planted into this mulch which suppresses weeds until the crop canopy cover closes providing additional weed suppression. Many farmers in Northampton and Lehigh Counties have heard about and seen the success of Rodale’s organic no-tillage system. However, many state skepticism about the use and practicality of such a technique on a working farm. Currently, it is critical to take the next step and move from the research farm to the production farm in order to assess whether weed control is effective and the economic benefits outweigh costs. 1. Monfreda, C., N. Ramankutty, and J.A. Foley, Farming the planet: 2. Geographic distribution of crop areas, yields, physiological types, and net primary production in the year 2000. Global Biogeochemical Cycles, 2008. 22(1). 2. Roberts, E.M., et al., Maternal residence near agricultural pesticide applications and autism spectrum disorders among children in the California Central Valley. Environmental Health Perspectives, 2007. 115(10): p. 1482-1489. 3. Tilman, D., Global environmental impacts of agricultural expansion: The need for sustainable and efficient practices. Proceedings of the National Academy of Sciences of the United States of America, 1999. 96(11): p. 5995-6000. 4. Turner, R.E. and N.N. Rabalais, Linking landscape and water quality in the Mississippi river basin for 200 years. Bioscience, 2003. 53(6): p. 563-572. 5. McLaughlin, A. and P. Mineau, The impact of agricultural practices on biodiversity. Agriculture Ecosystems & Environment, 1995. 55(3): p. 201-212. 6. Bai, Z.G., et al., Global Assessment of Land Degradation and Improvement Identification by remote sensing Report 2008/01. 2008, FAO/ISRIC: Rome/Wageningen. 7. West, T.O. and W.M. Post, Soil organic carbon sequestration rates by tillage and crop rotation: A global data analysis. Soil Science Society of America Journal, 2002. 66(6): p. 1930-1946. 8. ERS (2005) Agricultural Chemicals and Production Technology: Pest Management. ERS/ USDA Briefing Room. 9. Pimentel, D., et al., Environmental, energetic, and economic comparisons of organic and conventional farming systems. Bioscience, 2005. 55(7): p. 573-582. 10. Kornecki, T.S., A.J. Price, and R.L. Raper, Performance of different roller designs in terminating rye cover crop and reducing vibration. Applied Engineering in Agriculture, 2006. 22(5): p. 633-641. 11. Wilson, D. (2005) Choosing cover crops for no-till organic soybeans. The New Farm. 12. Moyer, J., Integrated cover crop innovations for biologically based no-till, in SARE agricultural research and education. 2007. 13. Luna, J., Managing Cover Crop and Conservation Tillage Systems To Enhance Vegetable Crop Yields, Economic Returns and Environmental Quality, in Sustainable Agriculture Research and Education. 2006.
Project objectives from proposal:
Rolled down cover crops can provide sufficient weed suppression to allow no-tillage organic production. Recent research by the Rodale Institute in Kutztown, PA has shown successful weed suppression by rolled down cover crops. This technique is relatively simple. Growers plant a fall cover crop mixture of rye and vetch or other appropriate cover crop and roll it down in the spring when covers have reached sufficient maturity to ensure cover crop kill. Then field crops are no-till drilled into the resulting thick mulch.
There are various types of roller equipment. We will used the roller crimper developed by the Rodale Institute which minimizes vibration and allows for greater tractor speeds . The roller will be front mounted which has been shown to improve kill for vetch and rye which otherwise springs back where tractor tires instead of the roller compress cover crops. Recent research shows that high plant populations in soy bean are an important element to weed control in the roll-down systems . We will plant at relatively high rates to ensure successful yields.
However, this technique has not been established by many farmers and questions remain, particularly timing of cover crop rolling, cover crop variety and species selection, and the effects of this technology on cash crop variety selection. Of farmers working with Rodale to try the technique two out of four had to abandon their trials due to drought or farmer oversight . In other regions on farm trials have been established  but these trials include cover crop species not suitable for the climate in this region.
Due to our close proximity to the Rodale Institute researcher Dave Wilson has agreed to consult with us on this project. This will allow us to build off of six years of research conducted at Rodale. Wilson will visit the site two times during the season and be available for consultation by phone.