Ag Source Lab in Ellsworth, Iowa: Examining the Impact of Cereal Rye Cover Crop Termination Date on Corn Seedling Disease and Yield

In an effort to better understand the long-term effects of cover crop practices on corn yields, Arlyn Kauffman conducted a study near Weldon in Clarke County. The research aimed to determine the effect of termination date of a cereal rye cover crop on corn seedling disease and yield.

The experiment involved three replicated treatments: a cereal rye cover crop terminated 15 days before planting (DBP) corn, one terminated 0 days before planting (on the same day), and another terminated 70 lb/ac using a drill. The first termination date occurred on April 15, 2017, while the second termination date took place on May 8, with an application of glyphosate at a rate of 32 oz/ac.

The study found that terminating the cover crop 0 days before planting corn resulted in significant corn yield reductions compared to when the cover crop was terminated 15 DBP. In fact, research conducted by scientists in North Carolina and Iowa has consistently shown that terminating a cover crop within a few days of planting corn can lead to reduced yields.

In three out of four trials involving these studies, planting green resulted in corn yields reduced by 3-12% compared to when the cover crop was terminated 14-21 DBP. Recent on-farm research by PFI cooperators Dick Sloan and Tim Sieren has also tested the effects of 'planting green,' which involves planting corn within two days of terminating a cover crop.

The study's results provide valuable insights for farmers considering incorporating cereal rye cover crops into their rotation. By understanding the impact of termination date on corn yields, growers can make informed decisions about their cover crop practices and optimize their cropping systems for improved outcomes.

Ag source lab ellsworth iowa