Penn State Interseeder Project Update
Posted: July 2, 2013
The latest Penn State Cover Crop Interseeder is capable of seeding the cover crop, applying nitrogen fertilizer and a postemergence herbicide all in a single pass. (Image courtesy of William Curran).
Some of you know about our cover crop interseeder work that has been developing over the last several years. Of course the idea is to establish a cover crop in early summer in cash crops where fall establishment opportunities are limited. Corn grain has been our primary target, but we are also interested in soybean and perhaps other crops planted in 30-inch rows. We have been testing annual ryegrass and some clover species. In corn, we operate the interseeder when the crop would typically receive an application of side-dress nitrogen, so generally between V-6 and V-8, although we are still trying to fine-tune the timing. Our interseeder is designed to not only seed cover crop, but also apply side-dress N and a postemergence herbicide, if needed. We are on our third design innovation with the interseeder, with the latest model using double-disk openers operating very much like a no-till drill (see image 1).
We received a USDA-NRCS Conservation Innovation Grant (CIG) this past year that will run for three years to further investigate this technology in PA, MD, and NY. The interseeder will be run both in replicated trials at our research farms and in farm fields around the Northeast. We are collaborating with Cornell University, the USDA-ARS in Beltsville, county-based extension educators and others. We have at least 15 on-farm trials that have been going out over the three-state region in the last few weeks that include both legumes and grasses. We are also involved in some research trials in northern New York and Vermont. In addition to the on-farm work, we are investigating annual ryegrass varieties and comparing different grass and legume species for their success with this technology.
For the most part, the recent ample rainfall has provided very favorable conditions for cover crop germination and emergence (see image 2), as long as flooding was not an issue. Of course to be successful, the cover crop must survive under the crop canopy through the summer and fall and hopefully take off once corn growth slows and after the crop is harvested. Ideally, the cover crop persists over the winter and continues to grow in the spring before being terminated with herbicide or tillage and the next cash crop is planted. There are many potential benefits, including erosion protection, nutrient sequestration or N fixation, grazing opportunities, improved soil quality, etc. Stay tuned for additional updates as this project progresses.
Legume-grass mix inter-seeded in corn at the James Eby Farm, Lancaster County PA. (Image taken on June 27, 2013 courtesy of James Eby).