Tag Archives: cover crops

Understanding the Nitrogen Advantage of Annual Ryegrass

Let’s review the facts about nitrogen, in the context of growing corn in the Midwest, and the connection to ryegrass as a cover crop.

One, corn needs a lot of nitrogen, and if corn is planted year after year in the same field, you will need to add nitrogen to bring the corn to harvest.

You already know that no-till will help stabilize the soil and help it regain its natural health. However, unless you plant a cover crop, you will continue to have to add a lot of nitrogen to feed the corn.

Secondly, it’s known that annual ryegrass “sequesters” nitrogen. As it grows, annual ryegrass absorbs available nitrogen from the soil and then sequesters, or stores, the nutrient in the foliage. When the cover crop is terminated in the spring, all that residual, stored up nitrogen is released. Annual ryegrass, because of its leaf structure, decays quickly in the spring, thus making its nitrogen available to the new corn as it begins to mature in late spring.

Lots of study has been done in the past 10 years about how much nitrogen is absorbed by annual ryegrass, and how much it can contribute back to the corn plants when the grass decays.

At best, the nitrogen that annual ryegrass adds back to the field substantially reduces the need to supplement nitrogen during the year. And, at a minimum, annual ryegrass reduces the costs associated with planting and managing a cover crop.

In an experiment studying annual ryegrass, Farm Journal Field Agronomist Ken Ferrie recorded per-acre costs for annual ryegrass and then calculated the value of the residual nitrogen left over in the spring, when corn was planted. the following graphic box indicates the costs/acre for seed, machinery, herbicide and application costs for terminating the ryegrass.

At the bottom of the graphic box, Ferrie estimates that the amount of nitrogen added back to the soil from annual ryegrass was $75/acre. That is an average and some will experience less, especially if you are just adding cover crops to your management repertoire. However, some farmers have experienced better than $75/acre return of nitrogen from their annual ryegrass cover crop.

So, according to Ferrie, “after subtracting the value of the nitrogen saved, the total cost of the cover crop was $5.75 per acre.” Not bad, especially when you then factor in the added benefits of cover crops: improved soil structure, increased organic matter, increased water infiltration, controlled erosion and recycling additional nutrients, like Phosphorus (P) and Potassium (K). This “recycling” occurs due to annual ryegrass’s deep roots, which helps corn to develop deeper roots to access P and K from deeper soil structure.

Phosphorus is a major component in plant DNA and RNA. Phosphorus is important in root development, crop maturity and seed production. Potassium is required so than more than 80 enzymes in the plant can be activated. K is also important for a plant’s ability to withstand extremes temperatures, drought and pests. Potassium also increases water use efficiency.

Finally, those who plant cover crops consistently experience higher corn yields, which translates into a profit to the pocket as well as to the continued health of farm acreage.

Annual Ryegrass as a Forage Crop

The Alberta (Canada) Agriculture and Forestry department encourages livestock producers to plant annual ryegrass as a forage crop. Here’s a link to the entire article.

In essence, they say that ryegrass and other annual crops provide flexible feed sources for livestock. Ryegrass has the advantage of being a quick crop to grow to extend grazing in the fall and/or spring. It can be used as emergency forage if alfalfa is killed during the winter. It establishes quickly and produces a lot of forage in a short amount of time.Of course, excess can also be stockpiled as feed.

When managed intensively, ryegrass can be very productive, the article says. It goes on to say: The fact that the crop has little or no dormancy makes it an ideal fall pasture as it continues to grow and maintain its quality well into the fall, making them useful in extending the grazing season.

In areas with very cold winters, annual ryegrass will often be eliminated by winter weather. But if it does winter over, it grows back quickly in the spring for continued use by livestock. But if the crop will be replaced by corn, for example, eliminating the annual ryegrass is imperative. Click here to review the proper management of annual ryegrass in the spring.

Annual Ryegrass, a Question of Dormancy Answered

Annual ryegrass seed, as with most other seeds, has a protective device that maximizes its chances for successful germination. But it’s important to know about it, so that you can successfully grow the cover crop and be prepared to deal with any dormancy issues that arise.

Most ryegrass seed, used for cover cropping,is spread in the fall, after corn and soybean harvest. Sometimes, the weather or soil conditions are not ideal for seed germination. So, in some cases, the seed will lie dormant until better growing conditions exist.

But the idea of cover cropping is that you have fields covered year round, so as to prevent water and nutrient runoff. Thus, having your cover crop germinate in the fall is important.

Newer varieties of annual ryegrass have been developed for colder climates in the Midwest. And yet, getting the ryegrass to germinate and establish can be challenging, especially in late harvest years with sparse rainfall.

Those in more northern latitudes of the Corn Belt are now going to interseeding (seeding the cover crop into standing corn in the spring, when corn is not yet knee-high – v 5 or so.) That can be done with high clearance equipment or by plane. This method avoids the perils of late fall seeding, though it does continue to require good seed-to-soil contact and moisture for germinating.

Oregon State University, a trusted research institution for grass seed science, has published a short paper about dormancy. It’s available on our website near the top of the list of Research links, and if you CLICK HERE you will find it easy to read and perhaps helpful.

Earth Fix Boosts Production and Profit

More than a decade ago, it was becoming clear that runoff from farm acreage was choking fresh water flowing south from the Canadian border to the Gulf of Mexico. Satellite images, water testing and production declines in fisheries pointed to a pending disaster if agricultural practices were not modified. At risk, the health of millions who depend on clean water, as well as industries that depend on healthy water.

Cover crops were introduced in a dozen states that border tributaries to the Mississippi, as well as along that great stretch leading into the Gulf. Last year, the Environmental Protection Agency produced a report for Congress outlining the “successes” in that gigantic project. Here’s a link to a summary.

Here’s one small result, from efforts in Indiana:

The 2014 fall transect [study] estimated 1 million acres of living plant cover such as cover crops and winter cereal grains were planted on Indiana farms. The report also shows most Indiana farmers left their tillage equipment in the shed in the fall to protect their fields with harvested crop residues. Results for residues and undisturbed soil on harvested acres during the winter months include: 77% of corn acres, 79% of small grain acres, and 82% of soybean acres.

The fall cover crop and tillage transect occurred again in 2015, and according to the data, over 1.1 million acres of cover crops were planted in 2015, which is an increase of nearly 10 percent compared to the previous year and 225 times more coverage over the past decade. The fall tillage and cover crop transect will be conducted again in late 2016.

Related image

In addition to keeping pollution from entering watersheds, the practice of cover cropping also makes a healthier environment for soil to heal. That, in turn, makes corn and soybean production more profitable, even in years when drought or low commodity prices carves into profits.

Ryegrass and other Cover Crops – Benefits the Purse and the Earth

You have undoubtedly read, or experienced, the following effects by stopping cultivation, adopting no-till agriculture practices and then planting cover crops, such as annual ryegrass.

Saving on fuel costs by reducing the trips over the field
Reducing or eliminating soil compaction and fragipan layers
Preventing soil erosion
Conserving soil moisture
Protecting water quality
Fixing atmospheric nitrogen while reducing the need for nitrogen fertilizer
Reducing the need for herbicides and pesticides
Improving organic matter, soil porosity and water infiltration
Increasing the population of healthy microorganisms and earthworms
Increasing yields by enhancing soil health

In the last year, another benefit has come to light, based on the collaborative work of two men working on opposite sides of the Atlantic ocean. They claim that cover crops help to mitigate the effects of climate change.

Professor Jason Kaye (Penn. State) and Miguel Quemada (Technical University of Madrid) looked at the following things:

Cover crops lower greenhouse gases by increasing soil carbon sequestration and, thus, the use of less fertilizer
Cover crop vegetation also lowers the proportion of energy from sunlight that is reflected off farm fields.

This last point, according to Professor Kaye, “may mitigate 12 to 46 grams of carbon per square meter per year over a 100-year time horizon.” Click here to read a longer description of the article. Or, click here for the academic study itself.

Interseeding Annual Ryegrass

With more than half of the nation’s corn planted, it’s closing in on interseeding time. Once the corn is at v5 – v7, you should be able to seed annual ryegrass with a modified drill or another modified high-clearance piece of equipment.

The value of interseeding has now been proven out, from southern Canada on either side of the Great Lakes, to the I-70 corridor in the US. In that belt, it’s difficult to find enough growing time in the fall to plant a cover crop. So, planting into growing corn in the spring is proving to be a valuable alternative.

What is key in this phase of cover cropping is that the seed have enough moisture to germinate and establish, before the corn foliage canopy creates so much shade that the annual ryegrass goes semi-dormant.

Having the cover crop in place throughout the summer doesn’t take away much nutrition or moisture from the corn. That’s because the cover crop hasn’t the sunlight to produce much vegetative or root mass. After harvesting the corn in the fall, the cover crop having been established in the spring, now has more of a head start for a quick burst of growth in the fall before wintertime.

For more information on interseeding, check out this video, from the University of Pennsylvania.

Annual Ryegrass Burndown this Spring

“An ounce of prevention is worth a pound of cure.” Benjamin Franklin’s quip is just as sound today as it was when uttered 250 years ago.

The reason annual ryegrass has NOT become a problem in the Midwest, despite heavy use in the past 20 years as a cover crop, is because those using it have been careful in its use…or have been able to recover from their mistakes without too much extra trouble or expense.

So, what can go wrong?

You let it grow too long in the spring before killing it with an effective “burndown” with glyphosate or other herbicide. Ideally, spray the crop before it gets to the “joint” stag (6 inches or so in top growth)

You try to spray the crop before all the grass is in active growth mode. It’s important to wait until it has fully broken dormancy, perhaps a week after you notice the first growth, and after the daytime temperatures reach 55 – 60 degrees, and nighttime temperatures are consistently above 40 degrees.

You’ve used a cover crop mix and thus the dates to spray become variable because each plant (annual ryegrass, cereal rye, vetch, clover) recover from dormancy at different times.

You spray once but don’t kill it all off with one application. At that point, it pays to be vigilant. Letting a cover crop recover from one application of herbicide can give it tolerance to a second application. Thus, it’s very important to pay attention to the second application, in terms of products to use, timing of the application and assuring that the second burndown is effective.

For more details, contact neighbors or a trusted agronomist. And by all means, check out this free information about controlling annual ryegarss, from our website.2016 ARG as a Cover Crop – 4 page

More Buzz about the Value of Cover Crops

“The good news is, soil will improve every year you grow a cover crop,” said Dan Towery, a crop consultant, and owner of Ag Conservation Solutions, living in West Lafayette, Ind.. “How soon you see measurable yield improvement depends on field history and what limiting factors, such as weather, are present in a year. For example, soils that are low in organic matter will benefit faster from cover crops.”

His comments are part of a longer article in the Farm Journal online. Click here to view the whole article.

Ken Ferrie is also interviewed for the article. Ferrie, Farm Journal’s Field Agronomist said “It might take many years to make big changes in soil health, but in some situations, you might see improvement (earlier than that.). For example, he cited a study in which annual ryegrass as a cover crop improved carbon content, bulk density and water infiltration IN THE FIRST YEAR!.

“As with any new practice, you’ll be eager to determine whether cover crops are having an impact,” Ferrie says. “Your soil physical provides a benchmark so you can follow up later and see if soil health is improving.”

Another farmer and rancher, Gabe Brown, talked about the benefits of cover crops in North Dakota. “You should use covers to address your resource concerns,” advises Brown. For the past two decades, he’s used cover crops to increase diversity, build organic matter, and improve water infiltration and the water-holding capacity of his soils.

“We look at each field separately and determine what the resource concern of each field is,” he says.

But make sure you choose a cover crop with a lot of forethought and advice from others with experience. Otherwise, you may be inviting failure or added problems. “Cover crops take more management, not less,” said Mike Plumer, who died last Christmas after dedicating 50 years to soil health and farmer education. “Farmers have to learn how cover crops react on their own fields.”

Plumer advised producers to start small with cover crops – perhaps a 20 acre plot or so, before “before incorporating on the entire farm.”

Annual Ryegrass Eliminates Fragipan Scourge

Fragipan, that compacted soil preventing crop root penetration, covers an estimated 50 million acres of farmland in the eastern US.

Tillage, even deep ripping, didn’t begin to contend with the deeper compaction and layers of fragipan.

Then in the late 1990s, as the idea of no-till agriculture began to gain more attention, an Illinois farmer began to experiment with annual ryegrass to begin to contend with erosion on his hilly acreage.

Junior Upton, Jr. began with a test plot of annual ryegrass. Working with soil agronomist Mike Plumer (U. of Ill. Extension), they believed that annual ryegrass would grow well in low pH soil (like fragipan) and build organic matter because of the vast mat of roots thrown out by annual ryegrass.

He planted the grass seed after harvesting corn and then eliminated the crop a few weeks before planing corn again in the spring. In a Farm Journal story a few months ago, by Chris Bennett, he quoted Mike Plumer about that experience with Upton. “In just the first year of use, we saw (annual ryegrass) roots 24″ to 28″,” said Plumer. “The second year was 30″. After four years rooting, (the annual ryegrass root measurement) was at 60″ to 70″,” Plumer added. In normal fragipan, soybean roots often only reach 12″, but after five years of annual ryegrass, Plumer recorded soybean roots at 36”.

The article (click here to read the whole thing) goes on to say that after killing the annual ryegrass, the roots decay and leave a network of channels for corn or soybeans to occupy. With continuous no-till, the channels created by annual ryegrass allow corn and soybean roots to push deeper each year.

Another discovery: As root depth increases, yields also expand, as Plumer explained . “On Junior’s farm, we’ve got some fields 16 years in the making. His corn yields, before we started, were at a five-year average of 85 bu. per acre, but after six (additional) years (with annual ryegrass cover cropping), he was over 150 bu. per acre. After 10 years, he was over 200 bu. per acre, and it is all documented,” Plumer says.

And the miracle of annual ryegrass continued. As the depth of corn and soybean roots grew, Upton and Plumer measured a remarkable increase in soil nutrients being pulled from deeper soil up to service the crop. “The ryegrass went so deep and picked up phosphorus and potassium. We were doubling and tripling the phosphorus and potassium tests without making applications,” Plumer added.

Annual Ryegrass Eliminates the Effect of Fragipan