In this project, we evaluated the Penn State Cover Crop Interseeder on three farms in replicated trials and on one farm as a non replicated demonstration. The trials were designed to evaluate a legume and Italian ryegrass mixture compared to an Italian ryegrass seeding with or without a seed treatment designed to improve establishment. Establishment in the three replicated trials was less than desired in most cases and the seed treatment had little effect on improving establishment. Cover crop plant establishment averaged 4.1, 5.2 and 3.3 plants/sq. ft in the three trials. In the fall biomass yields average 923, 864 and 265 lbs DM per acre at the three sites. We interseeded annual ryegrass in border areas of each study and this consistently established better than the Italian ryegrass. We also noted significant recovery late in the season at most of the sites which demonstrated that with even low establishment plant counts, significant cover crops can establish in the fall. At the demonstration site, establishment was much better including with some of the alternative species we evaluated such as tillage radish. We conducted several outreach activities in the fall showcasing the trials and the some of the insights we gained into interseeding and are using the results as a steppingstone to future work with the interseeders. We estimated a potential economic advantage of interseeding, provided we could achieve a good establishment of clover/ryegrass mixture to be $41/acre in the first year and $83 acre in subsequent corn years that this system was used.
The objective of this study was to assess the potential of a seed treatment to improve the interseeding establishment of Italian ryegrass and also to evaluate a mix of clover and ryegrass compared to a single ryegrass intereseeding. We were also interested in identifying any issues that could help to improve the potential of interseeding cover crops in corn.