Conversations from the Field
ATTRA talks to movers and shakers in the sustainable ag movement
Conversations from the Field features interviews with sustainable agriculture leaders. It is designed to highlight successful practices, creative programs, and progressive ideas, and to encourage readers to develop a more comprehensive understanding of the sustainable ag movement. We welcome your feedback on Conversations from the Field.
The Rodale Institute, Part 1 of 2
Jeff Moyer — Farm Manager
Jeff Moyer is The Rodale Institute's (TRI) Farm Manager in Kutztown, Pennsylvania. For over thirty years, Jeff has worked at TRI to develop more regenerative food systems that improve environmental and human health. TRI is a 333-acre farm where Jeff works to continually develop appropriate methods for reduced tillage in organic farming systems. This Conversations from the Field is the first installment of a 2-part series on cover crop and reduced-tillage research at The Rodale Institute. For this installment, NCAT agriculture specialist Andy Pressman talked with Jeff, last September, about reduced and no-till practices and the invention of the cover crop roller at TRI. The next installment will be an interview with Dave Wilson, the Rodale Institute Agronomist, about their on-farm reduced tillage research.
Q. Can you describe how the concept of reduced tillage came about at TRI?
A. Back in the mid 1980s we were doing a lot of chisel plow and off-set or heavy disk work when we began to think about ways to reduce tillage in organic systems. We began to look at different tillages and cover crops and the concept of organic no-till. One day, I was driving over a research field to till in hairy vetch for planting corn. When it came time for planting corn the following day, I noticed that the "rolled" hairy vetch was dead on the edges of the field where I drove over but did not till, and that the corn planter was able to plant through the vetch. I planted in the vetch and when the corn began to grow, there were no weeds. It was a complete accident.
Q. What is the relationship between reduced tillage and cover crops?
A. When you decrease one thing, you have to increase something else. When we reduced tillage without increasing anything else, the weeds began to take over. Other farmers at this time who were interested in reduced tillage would increase their herbicide use. That was not an option for us. So we increased our use of cover crops to supply nutrients, build organic matter, prevent soil erosion, and suppress weeds. Suddenly, our system began to improve.
Q. How does the rolling technique benefit the system?
A. We knew that we couldn't continue to just drive over fields, let alone recommend this to other farmers. But what we did know was that we needed to simulate the rolling technique. It is a way to manage cover crops in such a way as to kill them with minimal disturbance to the soil.
Q. Were there any forerunners to the cover crop roller?
A. Tractor-pulled rollers did exist at the time. We tried a cultipacker, but it didn't give enough crushing action for a good kill rate. Then we tried a Buffalo stalk chopper which created many problems. Although it knocked the cover crop down, it caused a lot of disturbance to the soil. It also has many moving parts that would get clogged by the hairy vetch. Another problem was that if the soil was moist, the tractor tires would make an indenture in the soil and the chopper could not reach the hairy vetch in the tire marks.
Q. Is this a problem with all cover crops or just hairy vetch?
A. With some crops this isn't a concern, but with vetch, it is a problem because in our temperate climate, vetch is aggressive and viney when wheat is planted in the system, and it will pull the wheat down. Hairy vetch seeds also mature at the same time as the wheat so the seeds end up in the wheat when combined. This isn't a problem if the wheat is used for livestock feed, but most mills won't accept it for human consumption.
Q. What was the solution for rolling cover crops?
A. We knew that roller needed to be hitched on the front of tractor and be pushed through the field. The first thing to touch the field needed to be the roller itself and not the tractor. By putting it in front of tractor, we solved this problem.
Q. How did this solution allow you to reduce your tillage?
A. We were now able to pull a planter or any no-till implement behind the tractor. By pushing the roller and pulling the planter, we just went from a two-pass operation to a one-pass operation with only the harvest remaining. For our corn and soy fields, this eliminated a nine-pass system of plowing, disking, packing, planting, two rotary hoeings, two cultivations, and the harvest. Now we have one pass to roll and plant and the other to harvest.
Q. Can you describe the roller?
A. The roller is a cylinder with curving blades that are 7 inches apart. The blades are arranged in a chevron pattern in order to have one blade continuously touching the ground at any one time. The blades are 4 inches. We thought that 2 inches wouldn't be enough and 6 inches seemed like too much. The blades are mounted back about 7 to 10 degrees so that they don't kick the soil. This also distributes the weight of the roller evenly so that the weight isn't on a single blade. The roller is also filled with water for added weight.
Q. Should the blades be sharp?
|To see a sample of different roller systems, visit the New Farm Roller Crimper Gallery.|
A. No. We don't want to cut the cover crop. We want to crimp it and knock it down. As long as the crop is attached to the ground, the planter will go through it.
Q. What plants can be rolled?
A. Our goal in this type of system is to target winter annuals. To name a few, we've rolled buckwheat, rye, sunflowers, and Austrian winter peas. Buckwheat is nice for vegetable farmers because they can plant it and in 6 to 8 weeks, roll it and no-till fall broccoli.
Q. Should the allelopathic qualities of rye be of concern?
A. The allelopathic effects of rye are more geared towards small seeds and grasses. I would never roll rye and plant carrots. However, we have seen no issues with rolling rye and planting, corn, soybeans, or squashes and pumpkins.
Q. Are there certain crops that shouldn't be rolled?
A. A good rule of thumb to go by is that if you step on the plant and it dies, this technology will work. If you step on it and it doesn't die, then you need to consider other options. This will not kill thistles, alfalfa, or perennial weeds. However, we have had success with rye and buckwheat choking out thistles.
Q. Is the timing of rolling important?
A. Absolutely. We only want to roll winter annuals in full bloom. During full bloom, the plant enzymes change, which makes it very easy to kill. If you roll too early, the plant is going to try and stand up and reproduce.
Q. Are there any challenges to targeting full bloom?
A. Well, it's a waiting game. While you're neighbors may be out plowing or planting, you're sitting on your porch, reading the newspaper, waiting for your cover crop to mature. Talk about nerve racking. Not to mention that it makes you look lazy.
Q. Has any of your research focused on the amount of cover crop needed for optimum performance?
A. Of course. For weed suppression this system needs at least 5,000 pounds of dry matter. This amount may affect whether or not the planter can get through the mat of rolled cover crop. We haven't had any issues with hairy vetch, but rye can be a problem. But then the question becomes is there too much cover crop for the system or too much for our planter? I think this is more of an engineering issue. In any case, if there is a bare spot, there will be weeds.
Q. Have you noticed a decrease in weed populations over time in this system?
A. Yes. But we aren't doing continuous no-till at TRI. After 2 or 3 years of no-till, there are breakdowns in the system. At this point we usually come through with a moldboard plow. Our theory is that we are rotating tillages; if we can no-till, we will and if we need to plow, we'll plow. If we can reduce or eliminate tillage in the system 2 years out of a 5-year rotation, we've saved about 40% of tillage.
Q. How does this affect production?
A. Take a look at our 2006 records. Our production fields averaged 160 bushels of corn (per acre) on our organic no-till and where we plowed and had all those passes, we harvested 142 bushels. So we not only harvested more corn through organic no-till, we made 7 less trips over the field. And there were fewer weeds, which results in the corn being cleaner and requires less work. It's much better economically.
Q. Is this technology advantageous for only organic farmers?
A. No. If you are a conventional farmer who is planting Roundup Ready® Soybeans, why not plant rye in the fall? Once you roll the rye and plant the beans, sit back and watch how very few weeds grow. Then you can spray Roundup®. Not only are you protecting the soil and building organic matter by using cover crops, but hopefully you're reducing the amount of pesticide applications.
Q. Why do you feel that the cover crop roller is an appropriate technology?
A. This is a scale-neutral technology. Farmers shouldn't get discouraged when looking at TRI and think that rolling and no-till won't work on their farm because they don't have the equipment we have. A farmer doesn't need the exact equipment that we use; they just need to think in engineering terms. Many farmers throughout the country have developed and/or modified rollers to fit their farm. I know a farmer in Vermont who made a "hand-held" roller for use in his greenhouse.
Q. Is there research on cover crop rollers happening elsewhere?
A. We are working with farmers and researches throughout the country: Michigan, Pennsylvania, North Dakota, North Carolina, California... The problem in California is water management. How much irrigation do you have to put on a cover crop? How much water does this tie up in your system? California organic farmers are also looking for alternatives to using black plastic mulch on vegetables. One California farmer told me he rolled and transplanted and still had spotty weeds. However, it required less labor to hand weed than to pay labor costs for workers to pick up the black plastic at the end of the season.
Q. I heard you say a few years ago that when you first developed this technology, it changed the way you thought about the whole system. Can you elaborate?
A. You have to do a lot of planning. You have to think about where you are going to be planting a year or two in advance. In my mind, cover crops are the most important crops grown on a farm. So this changes the whole perspective of the system. I'm not worried about the cash crop, but rather the cover crop because it will dictate how the cash crop does. It's also a prioritization of energy. I put more energy into cover crops. This eliminates so much of the old way of thinking about cash crops because with this system all you have to do is plant and harvest.
Q. Is there a learning curve for using this technology?
A. Emotionally and practically. Based on the research from around the country, the more experience one has with the system, the better the success. But there is no recipe for success. Most of the learning is based on timing. Many farmers roll too early because they want to get their seed in early and they don't see the potential for success.
Q. Can you offer any advice on how to prioritize investing in this technology?
A. I would say that this technology is too advanced for beginning farmers or farmers transitioning to organics. They should start with tillage and work their way to roller/no-till practices. There are many tools in the toolbox and you have to start with the basics. Experienced farmers, especially organic, need to appreciate the importance of this technology and give it a try.
This page was last updated on: February 9, 2015