Category Archives: Soil Quality

Whipsaw Weather Calls for Prayers…and Cover Crops

The coldest April on record to the hottest May on record…the Midwest can’t catch a break! Now mid-summer, people wonder whether more radical weather or trade and tariff issues will derail the current crops in the field.

Perhaps this is slim solace for those worried about what’s in store from Mother Nature and the Government, but cover crops are one thing that can continue to bring balance and health to farm acreage.

Annual ryegrass, for example, is among the easiest cover crops to establish. Grown in Oregon, in soil known for its wet feet, annual ryegrass is suited to poor soil and poor growing conditions. Likewise, when the weather turns dry, corn roots can access deeper moisture because annual ryegrass has established channels through even hardpan soil.

Thus, to build your soil’s health is the best strategy, so that whatever comes, the productivity and yield on your acreage will be maximized by having a consistent practice of cover cropping.

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.

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.

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 Plugging Through another Winter

While the temperatures plunge and the snow whirls, annual ryegrass top growth has been dormant for months. But under the freeze, the annual ryegrass roots continue to flourish, adding depth, girth and mass to a system that builds healthy soil in numerous ways.

The depth of rooting alone is a benefit, because it opens channels in the soil profile. Those channels, next spring and summer, will allow corn roots to seek deeper veins of nutrition and moisture. Even in a dry year, corn that goes deep will continue to thrive. And, with any normal precipitation, those root channels will help the soil absorb the rainfall rather than allowing it to run off.

Annual ryegrass has an appetite for nitrogen, too, so it becomes a storehouse of nitrogen when it grows. Then, in the spring, after it is killed with herbicide (before planting corn or beans), the nitrogen stored in the residue becomes a fertilizer for the hungry corn plants. And the massive root structure of annual ryegrass, when it is killed, that mass degrades and decomposes, increasing the carbon content and organic matter in the soil, giving worms and microbiological organisms a food source.

Because of annual ryegrass’ nature to sequester nitrogen, it’s place in the crop rotation allows you to lighten up considerably on nitrogen inputs.

For more information about annual ryegrass, why it’s beneficial and how to manage it successfully as a cover crop, you can check out this free four-page management guide. Or you can click here to view a series of YouTube videos on the subject.

CTIC 2017 Report – Another Banner Year for Cover Crops – And a Double Win for You

The Conservation Technology Information Center (CTIC) published a 2017 report of another annual survey of people using cover crops. Here are the first paragraphs from the report:

Following the use of cover crops, farmers reported increased yields of corn, soybeans and wheat, and improvement in the control of herbicide-resistant weeds, according to a nationwide survey. In addition, the survey of 2,012 farmers showed acreage planted in cover crops has nearly doubled over the past five years.

Survey participants—88 percent of whom use cover crops—reported that after cover crops:

Corn yields increased an average of 2.3 bushels per acre, or 1.3 percent;
Soybean yields increased 2.1 bushels per acre, or 3.8 percent;
Wheat yields increased 1.9 bushels per acre, or 2.8 percent.

This is more confirmation about how cover crops are profitable. The bigger bottom line, however, is that the acreage on which we draw our income is becoming more healthy as a result of planting cover crops.

Here’s the website where you can view and download the entire study.

Ray Weil on Cover Crop Benefits

Ray Weil was a guest speaker at the 2017 National No-Tillage Conference in St. Louis. His presentation focused on how cover crops benefit soil nutrient levels not only in topsoils, but in lower depths as well.

Ray is a Univ. of Maryland professor and co-author of Nature and Properties of Soil.

Ray Weil

Here’s a link to the podcast he delivered this year.

Ray’s research has covered how cover crops influence soil nutrient profiles at various depths and optimal planting dates for cover crops, their effects on moisture retention and how compaction influences deep root penetration.

More Coverage – CTIC/SARE Report on Cover Crops

Since the first annual report issued by CTIC and SARE about usage of cover crops, in 2012, the average acreage planted in cover crops by survey respondents has more than doubled…from just over 200 acres to more than 450 this year. Click here to view the entire report.

The report said the continued rise in use of cover crops was surprising, given the low commodity prices. It suggested that motives beyond profit are in play. In fact, the report says that 86% of respondents said that soil health was the primary reason they invest in cover crops.

About 25% of the more than 2000 respondents said that cover crops are planted on most of their acreage (81 – 100%) with another 11% saying than between 60 and 80% is planted in cover crops.

More than half said that they saw soil benefits from the first year of cover crop use.

Almost 60% said they have “herbicide-resistant weeds” on their farm, and that planting cover crops helps to reduce those weeds significantly.

When asked which cover crops were most effective in controlling herbicide-resistant weeds, most said “mixes” of cover crops, which all contain annual ryegrass. The second most popular response was annual ryegrass itself.

Ryegrass Cover Crop

A Cover Crop that Builds Soil and Boosts Production