No-Till FAQs
Answers to frequently asked questions
about the No-Till Plus project

With the first growing season winding down on our No-Till Plus project, we wanted to find a way to organize what we’ve all been learning together into an easily accessible format, one that we can build upon as we learn more. So, we poured through the reader mail and came up with a list of frequently asked questions.

What are the major challenges of a no-till roller system?

What are some of the greatest advantages of a no-till roller system?

Explain the no-till roller system’s effect on soil biology. What about soil compaction?

Will no-till work with conventional row crops?

Can I no-till roll a weed-infested field?

Can I use the no-till roller on cover crops such as Marshall rye or sorghum Sudangrass? What about red clover before planting a pasture?

Can you explain why timing is so important when no-till rolling and how this relates to different types of cover crops?

How do I select the best cover crop(s) to use if I want to try organic no-till?

Can I use a no-till roller on a home- or market-garden scale? What about setting one up for a rototiller or garden tractor?

What is the benefit of rolling the cover crop instead of simply mowing it down?

NEW! Is no-till vegetable production possible?

NEW! How do you sow the cover crop? Is it no-till, too?

NEW! How can I use the manure and compost in my field without tilling these amendments in to incorporate them into the soil?

NEW! Will I have to make any modifications to my seeder in order to plant into a rolled-down cover crop?

NEW! Is the no-till roller system compatible with hilly farmland?


What are the major challenges of a no-till roller system?

Anytime we are asked to learn a new process there are unexpected challenges to overcome. The no-till into cover crops system is no different. One of the challenges is matching the cover crop to the cash crop so that timing and planting date issues are avoided. For example, we no-till corn into legumes to take advantage of the free nitrogen. Typically on our farm, we use hairy vetch as our legume of choice, since it does well in our climate. However, many of the vetch varieties seem to flower later than we'd like, often delaying corn planting till early June. Some of are collaborators are breeding for earlier maturing varieties to remedy this problem.

Another major challenge is to re-evaluate how you think about cover crops. They’re no longer “just a cover crop” but the most important component of your weed-management strategy and, in some cases, your primary source of nitrogen. Therefore your success in growing cash crops is directly dependent upon your ability to consistently grow excellent stands of cover crops.

And the last challenge has to do with the system itself and the tools (cover crop rollers and no-till planters) we use to manage them. Having the right tool for the job, using it correctly and at the right time to kill the cover crop, and then setting the planter to plant through the heavy residue are all key to the success of the system.


What are some of the greatest advantages of a no-till roller system?

  • Prevents soil erosion.
  • Builds organic matter in the soil.
  • Minimizes soil disturbance
  • Living root systems in soil stimulate microbial activity including mycorrhizae.
  • One-pass system saves time and energy.
  • Does not rely on pesticides like conventional no-till (explain that it’s actually “limited tillage” and why.
  • Creates biomass above and below the ground.
  • Conserves water.
  • Recycles nutrients.
  • Creates channels for water, air and nutrients.
  • Increases soil tilth.
  • Improves aggregate stability.

Explain the no-till roller system’s effect on soil biology. What about soil compaction?

Since our no-till system provides a continuous root zone (with the noted exception in the next paragraph), we create a very hospitable environment for the beneficial micro-and macro organisms that build up the soil and make water, air and nutrients more available to crop plants. This system also creates biomass, both above and below the ground, which adds organic matter that feeds these microbes and stimulates their activity. Some of the microbes (mycorrhizae fungi) produce hyphae, microscopic hairs that branch out from the root system up to 18 feet and produce glomulin, the “Super Glue” that binds soil particles and increases aggregate stability. The minimized soil disturbance also helps build up soil carbon reserves. When you also consider the benefits of better water infiltration and less erosion, it’s easy to see how soil health is improved.

As far as soil compaction goes, in our system we only no-till for two or three years in a row, then we use a plow. So, in that sense, we are not a true continuous no-till system. We mix no-till into a plow-till system to take advantage of both systems to manage weeds and improve soil health. Also by using this no-till technology in conjunction with cover crops, we’re able to reduce soil compaction over the course of our multi-year crop rotation.


Will no-till work with conventional row crops?

Yes, it works for corn and soybeans as well as with other traditional wide-row crops. We have made great improvements in the organic no-till system over the past five years. These have come in the form of better equipment to manage cover crops and to plant into them to establish the crop and suppress the weeds. The improved practice works well for growing our organic corn and soybeans. These practices also serve you if you use agricultural chemicals—such as herbicides or insecticides—by helping you cut down your use of them.

We are also working across the country to address the issues of cover crop selection and the related cultural practices to get the most out of them in terms of the system. There are now plans available for our roller and we have partnered with a local manufacturer who builds and sells rollers. This is the tool we designed at The Rodale Institute and have written about in New Farm (see the No-Till + Page for more on the roller and no-till research). With this tool and some planter modifications, the system has been shown to have great success.

We are in the process of field testing the equipment in seven regions of the country to gain experience with different cover crops, different soils, different climates and different farmers/managers. Within two years, we expect to have that data to better support farmers who want to move in this direction.


Can I no-till roll a weed-infested field?

Not without lots of herbicide. Let me explain what I mean. Our roller is really designed to work in combination with cover crops—specific cover crops that are “winter annuals.” These are crops like hairy vetch, rye, Austrian winter pea, wheat, barley, etc. And they are all crops that are generally planted in the fall, live through the winter, thrive in spring, and finally die back in summer and drop their seeds.

What our roller does is kill these crops early—once they have physiologically reproduced, but before the seeds are ripe. So, in effect, we are working with nature to better time an event that will happen naturally to suit our need to grow a crop and protect it from weed pressure. Now, as for weeds or perennial plants, our roller really won't do much to kill them. What will happen is that the roller will physically knock them down, the planter will go through the mat, and then the weeds will grow back and choke out the crop. That is why I said you'd need herbicide or tillage to kill the weeds.

In a conventional no-till system, we use herbicides to replace tillage to manage weeds. With our system, we use cover crops to replace tillage or herbicides.


Can I use the no-till roller on cover crops such as Marshall rye or sorghum Sudangrass? What about red clover before planting a pasture?

More than likely, you already have some existing vegetation where you expect to plant your pasture. The roller we have designed works to kill “winter-annual” cover crops by crimping their stems once they have flowered to create a dense mulch layer that prevents weeds from germinating.

The system is not designed to kill annual or perennial weeds or ground covers. Therefore, if you have an existing pasture or weedy areas, it will do very little to help get a pasture established.

If your land is organic or chemical free, you will need to perform some sort of tillage activity to establish a new pasture. If you plan to use a chemical treatment, check with your county extension agent for the best strategy to remove what is existing, or knock it back to plant your pasture mix.

Red clover is a bi-annual and not recommended for this system. We have seen this year where short rye isn't staying down like it should. We have rolled barley and wheat in the past; they were short -strawed varieties and rolled nicely. Often, a cover crop such as hairy vetch doesn't look great the day you roll it, but a week later you'll see it die down (if you waited until it was in full bloom).


Can you explain why timing is so important when no-till rolling and how this relates to different types of cover crops?

The biggest issue with timing is that you don’t want to roll your cover crop too early; this is an all-too-common mistake. If the cover crop is not at full maturity (as defined by initiating full reproductive status), it’s going to come right back to haunt you as a weed. Maturity varies by cover crop. With hairy vetch, you want to make sure at least 75 percent of the crop is flowering for a good kill. There should be immature seed pods at the bottom of the bloom area. With rye, you’re looking for a “milky dough” stage in the seed formation, where the seed pod has the consistency of milky dough or yogurt.


How do I select the best cover crop(s) to use if I want to try organic no-till?

Your cover crop and cash crop must be a good match, timing wise, with respect to your goals and your growing region. Variables to consider include biomass (how many pounds produced per acre) and when the cover crop in question comes to maturity. Hairy vetch is an excellent choice as far as the way it behaves when rolled down, but it’s not a good match for the South because it matures too late with respect to the cash-crop season. Crimson clover is a better choice for Southern climates, though as you move northward this cover crop is not able to put on enough biomass for adequate weed suppression, or for providing adequate nitrogen to support good yields. While we’ve had great success planting corn into rolled-down hairy vetch in early June here in southeastern Pennsylvania, for some farmers this just isn’t early enough (plant breeders are working on earlier-maturing varieties of this cover crop with some level of success). So your choices really depend on a combination of what will work in your growing region and your own personal goals. They also depend on the type of cash crop you are growing.

Soybeans, for instance, being legumes themselves don’t need a legume as a cover crop. Rye works very well as a rolled-down cover for this crop. We’re also experimenting with rye, wheat, oats and barley as possible winter-annual cover crops suitable for rolling. Many of these grain covers will work for pumpkins, vine vegetables like cucumbers or squash, or even string beans.

The goal always needs to be matching the cover crop needs and expectations to the cash crop in terms of timing (when is each planted and when does each mature), nutritional needs (does the cash crop require a legume as a cover), and water requirements, since some crops like rye tend to have a high water demand (an important consideration in arid climates).


Can I use a no-till roller on a home- or market-garden scale? What about setting one up for a rototiller or garden tractor?

Our no-till roller is set up to be front-mounted on a tractor with the seed-planter on the rear for a one-pass system that saves time and fuel. Of course, the smaller an area you are planting the less critical these concerns become. J.I. and Bob Rodale developed their regenerative farming techniques with the idea that farmers could and should apply the same care to their fields that organic gardeners apply to their gardens. Cover crops are certainly an integral part of a home or market garden as they are any farm, and the same advantages of rolling them down—namely, providing a weed-suppressing mulch over a longer period of time—exist in both environments. Indeed, cover crop rollers can come in all shapes and sizes; just visit our roller/crimper gallery and see for yourself You’ll find one mounted on a large garden tractor; pulling one with a front- or rear-tine tiller might be a little trickier. However you could easily design and built one that could be small enough to pull by hand. The idea is to bend the cover crop plant over and crimp the stem every 6 to 7 inches along its length. Any tool that does this has a good chance of being effective.

As for planting vegetable crops, you should be able to transplant or direct seed into the system depending on what you want to plant and what cover crops you have available to you. For example we are direct seeding pumpkins into hairy vetch. You could also direct seed cucumbers or squash the same way. Small seeded plants like lettuce or carrots would be much more difficult but not impossible (lettuce plugs or seedlings are probably the way to go). If you have a more sophisticated planter, like a Monosem no-till vacuum planter you could get the seeds in the ground, but getting them up through the mulch of the rolled cover crop may be tough (that’s something we’ve never tried). Ron Morse, PhD, at Virginia Tech has done quite a bit of no-till veggies into cover crops as has Jeff Mitchell, PhD, at the University of California, Davis. Both of these researchers and several farmer co-operators are successfully no-till transplanting crops like tomato, eggplant, cabbage, etc., into these systems.


What is the benefit of rolling the cover crop instead of simply mowing it down?

There are several key differences that occur in the system when a mowing action is used instead of rolling/crimping. First, if we use a mower, the cover crop material is cut into small pieces. This action encourages more rapid decomposition of the plant material. This is something you don’t want since you will be depending on the mulching effect of this plant material to suppress weed germination. The second problem we’ve experienced is that once the cover crop is actually severed from the ground and becomes loose material sitting on the soil surface, it becomes an impediment to the planter which will simply drag the cover crop up into piles.

Our roller, on the other hand, is designed to crimp off the vascular system of the plant stems every seven inches, effectively killing the cover crop (as long as it’s in full boom). Leaving the plant attached to the ground allows the planter to move freely through the field and slows down the decomposition process.


Is no-till vegetable production possible?

Yes, you can transplant or direct seed right into a rolled-down cover crop. Our experience here at The Rodale Institute is currently limited to direct seeding pumpkins, corn and soybeans into hairy vetch, a mixture of vetch and oats, and rye. But others around the country have been working with other vegetable-crop/cover-crop combinations in organic no-till systems (see our no till research updates in the December 2006 issue of New Farm for some examples).

Ron Morse, PhD, a professor of horticulture at Virginia Tech, has pioneered research into organic no-till vegetable production, experimenting with broccoli, potatoes, tomatoes, cabbage and other vegetables planted into a variety of high-biomass cover crop mixtures. One of the keys to his success was the creation in 1990 of a “Sub-Surface Tiller-Transplanter.” The front component is a durable sub-surface tiller that prepares a narrow strip of soil, loosening it as deep as 8 inches. Next in line is a no-till transplanter that sets transplants into the prepared strip. The press wheels of a double-disk opener ahead of the planting shoe are modified to close the untilled soil around the plant. Like our work here on our farm, it’s all about finding—or making—the right tool for the job. To find out more about Dr. Morse’s work with organic no-till vegetables, see the article Organic no-till for vegetable production?

Jeff Mitchell, PhD, is doing similar work on the research station at the Kearney Research and Extension Station in Parlier, California, as well as working directly on growers' farms in the region. He’s also one of the collaborators on our No-Till Plus Project.


How do you sow the cover crop? Is it no-till, too?

Ours is actually a limited tillage system, as we do till in the fall to plant the cover crop. We are organic and we are rotational, so the no-till crop is not continuous as with conventional no-till.

We have tried no-tilling the cover crops in this system in the past and found the weed pressure to be too overwhelming. We do no-till cover crop—say rye into corn or soybean stubble—in situations where we’ll be plowing the crop under in the spring; this would then be planted to spring oats. But in a situation where we’re planting that cover crop to be rolled for organic no-till, we like to start with a clean seedbed in the fall. It is very important to have an excellent stand of whatever cover crop you plant, since this will be your primary defense against weed seeds germinating. The same cover may also be your primary source of nitrogen in the system, making it that much more important for the cover crop to be well established. Therefore we take whatever steps we need to in order to ensure a solid stand of our cover crop.


How can I use the manure and compost in my field without tilling these amendments in to incorporate them into the soil?

In our rotation, we typically apply compost to our fields following wheat or oat harvest. We only do this every five years, at a rate of 8-10 tons/acre. Then we plow it under and plant the fall crop.

Compost can be surface applied but typically you will not gain as much benefit as when you incorporate it. Manure should be incorporated because you can lose a lot of nitrogen due to volatilization. Surface-applied compost and manure are both subject to runoff in the rainy season, though compost is more stable so this is less of a problem. There are several new tools on the market to knife-in the manure for no-till systems, but in our system—where we still incorporate tillage at some points in the rotation—we apply the manure ahead of the tillage.


Will I have to make any modifications to my seeder in order to plant into a rolled-down cover crop?

Yes, more than likely. You may need to apply more weight to have the force necessary to cut through the thick rolled-down mat. The depth of the double-disk openers will also need to be adjusted in order to adequately cut through the mat and then into the soil. Oftentimes we find that the seed furrow that is cut does not close as easily in a no-till system with all this residue as it does in a tilled system. Therefore, we upgraded the press wheels on the rear of our planter from rubber to cast-iron to ensure adequate seed furrow closing and proper seed-to-soil contact. These considerations change depending on your soil type; observation and adjustment are going to be critical to your success.


Is the no-till roller system compatible with hilly farmland?

Yes, and you’ll still want to be certain that you farm along the contour of the hill. This may be slightly more challenging than farming on flat land, but it is certainly manageable. In fact, reducing tillage on sloping fields is a great way to preserve and protect your soil. I generally start my planting operation on the uphill portion of the field and work my way down slope to allow for any possible drifting of the tractor due to the gravitational pull of the equipment. If all goes well, your crops will do just fine, and not needing to cultivate along the hill will save you time and extra aggravation.