ASK Jeff: The Rodale Institute’s farm manager, Jeff Moyer, answers your hardcore farming questions

Will your cover crop roller provide enough kill?

Posted December 8, 2005

What Jeff brings to the table

Jeff Moyer, who’s been the farm manager here at the 333-acre Rodale Institute research farm for more than a quarter of a century, receives lots of mail from farmers just like you asking for advice. Jeff’s hands-in-the-dirt experience over the past 26 years has run the gamut from refining the farm's cover cropping and crop rotation systems (including managing 270 acres in a rotation of corn, small grains, hay, and edible soy beans for a Japanese market) to overseeing The Rodale Institue Farming Systems Trial®, the world’s longest running side-by-side comparison of organic and conventional agriculture. We thought it would be fun and informative to share some of these farmer-to-farmer exchanges, and Jeff’s practical wisdom, with our readers … and we’ll be doing it on a regular basis.

Got a question of your own? Send it to Jeff at:

Dear Jeff,

In regard to the use of rye as a cover crop into which soybeans are no-tilled the following spring: Because in southeastern South Dakota we are often dry, it is imperative that the rye mulch plant is killed so as not to compete with the soybeans. Does the roller accomplish this? If so, can I get plans to build my own roller?

Larry Eisenbeis
South Dakota

Dear Larry,

Thanks for the email and the interest in our cover crop work and organic no-till. The question you ask is very important and one that several others are concerned about.

Moisture is not nearly as critical here in the East as it is in spring for you folks. For that reason, we will be sending a roller to Steve Zwinger up in North Dakota at North Dakota State University. We currently don't have enough data for me to say what will fit into your system. I can tell you that the roller will kill rye but not until it is headed out, and that may be too late for you in terms of moisture.

Think of the roller as a tool to speed up the process of what a plant does naturally. For example, winter annuals like rye would normally die after it sets seed. We are simply tricking the plant into physiologically dying early by crimping the stem once it is past it's flowering stage. If you roll the rye to early, its need to flower will be too great and it will stand back up and continue to survive, although at a weaker stand (more like a gooseneck stand). If you roll it real early when it is only in the vegetative stage (grass), it will do nothing but leave marks in the soil. We need to get more data on the timing of rolling in moisture-sensitive areas as well as searching for other cover crops that might fit the system there better than rye.

Hope this helps.


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