In Oregon, the Democratically led legislature is trying to pass a bill that would pay overtime to farm workers for the first time. Despite frequently putting in overtime year-round, worker have never received time-and-a-half for hours worked beyond 40 per week.
A sign of fairness? A sign of inflation? As you might expect, employers are not happy with the prospect of more wages, on top of everything else that seems to be more expensive.
Speaking of inflation…fertilizer prices went up 200 to 300 percent in one year! What the heck is going on?
News today about a Congressional investigation into the astronomical increases in nitrogen and other fertilizers hit like a ton of rocks. Inflation in drug prices, land values and more have been constant. But 300 percent?
No doubt the cost of farming is going up, and there’s no guarantee that commodity prices will consistently follow that trend.
What’s a farmer to do about these rising prices if you’re wanting to hang in there, perhaps see the acreage being managed by your kids or grandkids?
Remember the slogan from the Goldrush days: “Eureka, We Hit Paydirt!”
Well, it’s becoming abundantly clear that annual ryegrass and other cover crops creat pay dirt. Here are the ways:
increases microbiology activity
increases organic matter
reduces annual weeds
improves crop yields
improves rooting depth in compacted soil
fattens your wallet!
It’s this last piece that should interest you the most. Because with the cost of N going through the roof, you can significantly reduce N inputs with annual ryegrass by itself, or in combination with other cover crop seed.
Planting a cover crop for the first time takes patience and a bit of money. But the investment will pay dividends immediately in a dry year and will continue to build value in the soil, without so many inputs.
Dan Olk went to the Philippines after earning his PhD at UC Davis, accepting a post-doctoral position with Dr. Ken Cassman at the International Rice Research Institute. They were investigating a global problem with declining rice productivity. “The plants were making use of fertilizer nitrogen but not soil nitrogen, despite the abundance of nitrogen in the soil,” he said. After years of study, they developed a winning strategy. By changing the seasonal management of rice crops and aerating the soil when the crop residues were decomposing, the trapped nitrogen could be released from organic matter. A few years later, a comparable project in Arkansas rice confirmed these results.
After joining the USDA in Iowa in 2001, Dr. Olk’s sleuthing continued to reveal why nutrients get bound up in soil chemistry, for rice growers internationally as well as domestic corn and soybean producers. Beyond his efforts to unleash the potential of organic matter, Olk has also spent many years investigating the use of “humic products” (made from young coal deposits) and their ability to stimulate plant growth.
annual ryegrass cover crop project in the Midwest had been rolling along for
more than 15 years when it came to Olk’s attention through the work of Dr.
Lloyd Murdock, who had been researching the effect of annual ryegrass cover
crops on fragipan soils located in Kentucky and Indiana. Olk and his USDA
colleague, Dana Dinnes, were presenting a seminar on humic products at the 2016
National No-Till conference. Murdock was receiving an award at the same
conference, and that’s when the men met. Murdock was being honored for his decades
of research on no till, which shows tremendous potential for boosting agricultural
productivity and soil health.
fragipan, a nearly impermeable layer of compacted soil, is so pervasive in the
US (50 million acres), the USDA has become interested in putting some of its
considerable heft behind this new discovery. Dr. Olk will lead a new research
project that will pick up where Murdock’s work at the University of Kentucky
you’re new to the story, here’s a quick summary: Junior Upton, working on his
southern Illinois farm for decades, discovered in the 1990s that annual
ryegrass added value to marginal land under which fragipan lay. Before trying
annual ryegrass as a cover crop, Junior noticed that corn roots would grow down
only to the edge of the fragipan layer (18 – 24 “deep) and then deflect
sideways, unable to penetrate.
corn in the fields covered by annual ryegrass began to outproduce neighboring
fields, especially in drier years, he asked agronomist Mike Plumer to help him
understand why. Plumer, then at the University of Illinois Extension, came out
with digging and soil coring equipment. In four-foot soil pits, they discovered
annual ryegrass had exceedingly long roots that grow throughout the winter,
even with scarce top growth. That was their first “aha!” The second one, which
now has the USDA’s interest, is that ryegrass roots pierced the compacted soil
and, thus, gave corn plants more rooting depth, additional nutrients, and
moisture. With that encouragement, Junior planted annual ryegrass on his entire
farm, year after year, and his soil health continued to improve as row crop yields
increased. When he first planted annual ryegrass and began collecting data on corn
production, his corn yield was 15 bushels per acre (bu/ac) below the county
average. In 2020, after 20 years of continuous no-till and annual ryegrass, the
same field produced 30 bu/ac more than the county average.
Murdock heard about Junior’s and Plumer’s discovery
and spent more than five years documenting what they were seeing in Junior’s
fields, as well as replicating field trials in four other farms in three states.
Murdock and his university team also took the experiments into greenhouses and their
laboratory to find out more about the chemistry and mechanics – trying to
understand why annual ryegrass seemed to degrade fragipan, where nothing
practical and sustainable was found to do that in the last half century of
research. His lab partner, Dr. Tasios Karathanasis,
submersed chunks of fragipan in several different solutions, one of which was a
“Within two to four
weeks we began to see the ryegrass extract break down the fragipan,” Karathanasis
said. They found
that annual ryegrass extracts were unique among all test solutions, the only
one to affect the integrity of fragipan. It led Murdock and his team to suggest
that annual ryegrass roots exude chemicals that loosen the molecular bond in
fragipan soil, which ryegrass roots then penetrate and pry away.
when Murdock added a humic product to his greenhouse tests, the annual ryegrass
appeared to have had an even greater impact on fragipan degradation.
Olk had met Murdock at the No Till conference in 2016, he had not become much more
familiar with the cover crop project, nor the people Murdock worked with,
including Junior Upton, Mike Plumer and John Pike, a research agronomist with
the University of Illinois. Then in 2021, the USDA lab where Olk works hired
Dr. Claire Phillips, who had academic roots in Oregon and who knew about the cover
crop work being done on Junior’s farm. In fact, she had met Mike Plumer on his Oregon
trips, where he reported on the cover crop project, including Murdock’s
research. Phillips made the introductions and the deeper connection to the USDA
research team began.
research will delve ever deeper into the mystery. In the 5-year project plan written to support the
research, Olk said: “Two proposed mechanisms (to demonstrate how fragipan is
weakened through annual ryegrass cropping) are that (1) ryegrass growth creates
a solution with a high sodium saturation ratio, which disperses fragipan
particles; and (2) ryegrass root
exudates contain chelating agents, which bind to aluminum and iron molecules in
the fragipan, thus helping to disintegrate those cementing agents within the
characteristic of fragipan is that it causes overly wet surface conditions
early in the growing season, due to poor natural drainage. Later in the season,
crops dry up because the shallow water supply evaporates or is absorbed quickly
by the crop.
USDA research will address that issue as well, relying on further field work in
a number of Midwest locations, including Junior’s farm in Illinois. Additional
lab and greenhouse research will continue in Kentucky, as well as at the USDA
labs in Iowa.
are more specifics as to the scope of Olk’s research, related specifically to
“We will look
more closely at the impacts of long-term artificial drainage on soil health.”
“We will study
the seasonal soil hydrology of corn-soybean rotations with and without annual
ryegrass winter cover crops. We will test the hypotheses that (1) ryegrass
growth removes excess soil moisture in springtime, and (2) it degrades the fragipan
sufficiently as to deepen the cash crop plant rooting zone, thereby increasing
plant-available soil water later in the growing season.”
“We will determine
the chemical composition of fragipans at varying stages of degradation by
annual ryegrass and humic product application”
“We will determine
the effects of a humic product on root exudates released by annual ryegrass in
a hydroponic (lab) system.”
his research, Murdock said the use of annual ryegrass, as a cover crop, could
dramatically change the output of crops on fragipan soils internationally.
Olk’s research will evaluate that claim. If proven true, annual ryegrass could
become an inexpensive method to add profit to formerly marginal acreage. It
would also help to lift a burden that has restricted agriculture on fragipan
soils for centuries.
38, is a fourth-generation family farmer from Metropolis, Illinois, whose story
unifies two things that characterize the growth of cover crops in the modern
era. The first is the importance of mentorship. The second is the role of “ah
ha” moments in our lives, which continue to fuel enthusiasm for progress and
productivity in agriculture.
case, as with others in this 25th anniversary tribute to annual
ryegrass as a cover crop, Mike Plumer’s influence as a teacher has been
crucial. And, as for those “ah-ha” moments, you’ve probably come to understand
that they occur in every life and every generation, often at the crossroads of
challenge and opportunity.
Bremer’s grandfather started a farm and cattle breeding business with his
brother after WW II, on what grew to 600 acres. His contribution to the
industry included the advancement of cattle breeding practices. Likewise, Marc’s
father (David) and grandfather were early adopters of no-till, working with the
nearby Illinois Extension at Dixon Springs. Marc’s contributions include the
widespread use of cover crops, annual ryegrass in particular, and how it has
compounded the farm’s success.
Brothers Farm seems wedded to the adage, “Work smarter, not harder.” Marc’s
great grandfather did that by doing his homework, becoming an avid record
keeper, and using that data to drive decisions. “After purchasing their first
Angus livestock in the 1950s,” Marc said, “we haven’t bought another female
since. My dad was working on a master’s degree in genetics from the University
of New Mexico when granddad passed away, prompting dad to come back to the
farming operation.” His academic work clearly complemented that which the
preceding generations had put to work. The science of breeding, combined with
their nutrient-rich, efficient feeding system, has made their herd one of
consistent quality and value, decade after decade.
decided in the mid-1960s that no-till would benefit the soil and keep it in
place. “With support from Dixon Springs Extension researchers, grandad started
using the no-till planting system to great effect,” Marc continued, “and
purchased a 6-row Allis Chalmers, which was among the first commercially-available
no-till planters. My dad followed suit, continuing to graze crop stubble on our
corn and bean acres after harvest. He
also started experimenting with cover crops in the 90s, then introduced grazing
onto those acres.”
was a friend of the Extension Agent working in that part of Illinois during
those years and became friends with the Bremer’s. That friendship extended to
the next generation when, in the early 2000s, Mike visited Marc in Wyoming to
hunt antelope on the ranch where Marc worked as a ranch hand and mechanic. In
order to be closer to family and move into leadership on Bremer Brothers Farm,
Marc moved back to Metropolis in 2010.
Mike had left the university and started a consulting business. By then, he had
learned about annual ryegrass and had helped others in southern Illinois add
cover crops to their operations. By then, he had partnered with the Oregon
Ryegrass Commission and was overseeing research trials in multiple Midwest
locations. Mike became more active as an educator as well, advising famers
about annual ryegrass at national ag shows and field day demonstrations.
embraced cover crops quickly and, like his father before him, invested in
equipment “to expand the farm without more land. We just learned to do better
with the 900 acres we had,” he said. After a couple of years using a 15’ Great
Plains drill, he purchased a 40’ drill that is pulled behind their 320 hp Cat
Challenger on tracks. From the early
days, towing a 6-row planter, the Bremer’s have now graduated to a 24-row Kenzi
“It may have
been as late as 2011 that Mike convinced me to use annual ryegrass because, by
then, he understood that it broke up fragipan soil which is prevalent in this
part of the country,” Marc said.
introduce annual ryegrass to the whole farm right away,” he added. “But during
the 2012 drought, we saw such a dramatic difference between acres planted in
annual ryegrass, versus plain no-till or with cereal rye, that we were
experimented too with whether livestock and grazing the cover crop would affect
the growth of annual ryegrass roots. “We brought out a 4’ soil probe and it
looked like grazing didn’t impact root growth at all. Compared to neighboring
property with no cover crops, it appears that annual ryegrass gradually gets
rid of fragipan, does a better job of suppressing weeds and, by having cattle
grazing the pastures, there are fewer slugs and voles to contend with.”
In a recent
study concluded by the University of Kentucky (Lloyd Murdock), Bremer’s farm
was shown to have gained more than 6 inches of new soil in seven years, simply
by having annual ryegrass as a cover crop, slowly reclaiming the layer occupied
by the otherwise impenetrable fragipan. In the same period, the amount of
organic matter increased from 2.0 to 3.5 percent.
recent “ah ha” for Marc was that when he terminated the cover crop early in the
spring, as he’d been strongly advised to, the fields would remain wet and
prolong the planting date of corn or beans. He thought if he let the cover
crops grow later, it would allow earlier planting. “I’ve experimented with
planting corn into cereal rye as tall as 7’ and annual ryegrass as high as 4 ½
feet. Then I’ll come back and terminate the cover crop, and for the most part
it still kills nicely,” he said. “I figure that even if there is some residual seed
from the cover crop, it will lay dormant under the corn until fall or can be
controlled with a post application of herbicide, which is fine too.”
Brothers Farm is part of the new round of research mentioned in the last
chapter, headed by USDA/Ag Research Service in Iowa. The research at Bremer’s has
two aspects: first, how the chemicals exuded by annual ryegrass roots degrade
fragipan, and secondly, studying the how grazing cattle on cover crop acreage
affects soil hydrology. “This research has widespread value for agriculture,”
Marc said, “to better understand nutrient cycling, and how soil holds
Marc and his
wife have three children, a daughter and two sons. One of the gifts Marc is
preparing for them, should they opt to take the farm into the next generation,
is that the land is now producing value 11 months of the year, rather than the
five or six months of many neighbors. “With cover crops and grazing cattle, the
land is more productive, and the soil is healthier,” he said. “Livestock and
cash crops work so well together. Annual ryegrass as a cover crop enriches the
soil, gets rid of compaction, and improves the water carrying capacity of the
soil. Cattle break down crop residue, provide nutrient-rich manure and get rid
of voles and slugs. Voles and slugs, as it turns out, can’t bench-press a cow,”
he added with a laugh.
arrived from Wyoming in 2010, we had 90 cow/calf pairs and 210 in inventory. To
support that herd, we were feeding them 100 tons of hay a year. Today, we have
about 110 cow/calf pairs and 275 in inventory. But we’re feeding them less than
90 tons of hay. The difference is that they’re getting fed by grazing cover
crops. We’re more profitable, the soil is healthier, and our corn and bean
yields are higher. Like my dad and granddad said, ‘You don’t necessarily have
to buy more land to expand your business.’”
“There is no known abatement of fragipan,” said Dr. Phillips
Phillips, a researcher with the USDA’s Agriculture Research Service (ARS) in
Ames, Iowa. “Until now, that is,” she added. “Annual ryegrass is a good one,
because the chemicals in ryegrass roots break down fragipan.”
Phillips and the congressionally-funded ARS are delving
deeper into the mystery of why annual ryegrass has this effect on fragipan. She
said there are 50 million acres of agricultural crop land impacted by fragipan
in the U.S. alone. “And fragipans are a problem around the globe,” she added.
Phillips and colleagues have proposed work to follow that of
Lloyd Murdock, who for the past decade has been documenting and testing the
effect of annual ryegrass on fragipan in laboratory settings and in the field. Murdock’s research
at the University of Kentucky found that a chemical exudate from ryegrass roots
is the reason. Specifically, the chemical excretion from annual ryegrass roots
systematically changes the chemistry and make-up of that compacted soil,
effectively reducing the presence of fragipan. In the following graph, taken
from Murdock’s study, you can see how annual ryegrass reduced the depth of
fragipan and increased the depth of healthy soil in five locations in two
Phillips is leading a five-year study
on annual ryegrass’ effects and how to augment them. “A key part of our
research will quantify how annual ryegrass, used as a cover crop, affects the
amount and availability of water in the field,” she said. “By reducing
fragipan, we may be improving drainage and thus expanding the window for
planting in the springtime,” Phillips added. “And we think that reducing
fragipan will make more soil water available during the summer too, by
increasing root depth. We want to measure how much more available soil water is
present, and whether the crop can put on more leaf area and experience less water
John Pike, a former University of
Illinois ag research manager, will be monitoring the study in Illinois, funded
by the Oregon Ryegrass Seed Growers Commission.
“Mike Plumer and other pioneers showed that annual ryegrass
can be really useful in Southern Illinois, Missouri, and Kentucky,” Phillips said.
“As our weather continues to change, ryegrass could increasingly be seen as a
‘climate adaption tool.’ Specifically,” she explained, “in the Midwest we’re
having more rain in the spring, and the rain events are bigger. I hope annual
ryegrass’ ability to reduce fragipan will allow more water to be absorbed into
the field instead of running off. So, even with more rain, farmers will be able
to get into the field in a timely fashion, simply because the water will infiltrate
more quickly rather than pooling or creating erosion.”
“Additionally,” Phillips continued, “the month of July in
the Midwest is becoming hotter and dryer than in the past. July is when the corn
most needs moisture. Annual ryegrass, by helping to create deeper soils may be able
to make up for that reduced precipitation.”
Phillips’s colleague, Dr. Dan Olk, will lead complementary
studies on how annual ryegrass chemically degrades fragipan. Olk, a biochemist,
is an expert on humic products, which are derived from young coal deposits and
are thought to enhance plant growth. Hypothetically, humic products used in
conjunction with annual ryegrass may have a compounding effect on the decay of
fragipan and enhancement of crop health. Phillips and Olk will look at samples
of fragipan soil collected from Kentucky and Illinois in different stages of
degradation. “We want to find out how the chemistry of fragipan changes at
different stages of breaking down, and whether humic products change the rate
of fragipan disintegration,” Phillips said.
While Phillips is focused on the science and field work,
John Pike will also be sharing the educational aspects of the work with a
variety of audience, from field day demonstrations to trade shows. Phillips
acknowledged the importance of a team approach to this and other projects. “I’m
very thankful to those who are partnering with us in our efforts, like John
Pike, the Oregon Ryegrass Commission, and Oregon seed growers, who continue
their on the ground support for this work.” She also acknowledged Ryan Hayes, an
ARS colleague who works on plant breeding at Oregon State University, where she
worked before moving to Iowa in 2020.
Some worry about how the adoption of cover cropping and
regenerative agriculture will keep expanding, as a generation of cover crop pioneers
like Mike Plumer and Lloyd Murdock retire. It is refreshing to see the next
generation of growers and scientists, like Phillips, stepping in to develop the
place-specific knowledge necessary to make cover cropping work in a challenging
environment where it can have the most benefit.
As a youngster, John Pike watched Mike Plumer excavate a small pit in a
cornfield not far from his own family farm in southern Illinois. Plumer, at the
time, was an Extension agent at the University of Illinois. “He was there to demonstrate how the fragipan
soil common to southern Illinois prevents healthy root growth and negatively
impacts crop yields,” John said. “The pit clearly showed corn roots hitting the
fragipan but not penetrating it.”
At the time, Plumer
hadn’t discovered how annual ryegrass, used as a cover crop, gradually breaks
down fragipan and allows deeper root growth. “But even then, before he made
that connection, his curiosity and deep conviction in conservation tillage made
a big impression on me,” John added.
That field day
demonstration stuck with John as he later attended college and followed in Plumer’s
footsteps at the U of Illinois, becoming an Extension agent and later a
research agronomist for the Department of Crop Sciences, in charge of research
station operations in the southern part of the state. “It was such a pleasure
to have the opportunity to know Mike as a friend and to work with him
professionally, before and after his retirement,” he said.
John’s career with
the university focused on soil fertility, nutrient management, and water
quality. Cover crop research became a significant part of that work. When the
university shut down four of its research stations, John started his own ag
consultancy as a research agronomist. And that, he said, led to “a more
flexible and comprehensive range of work,” a lot of which involves working
closely with researchers from other universities.
historically been a major source of innovation for the ag industry,” John
continued. “But with cover crop discoveries, it was largely the reverse, with
innovation coming from the field and gradually informing the universities to
backfill with research that quantified the benefits.”
He went on to
explain why. “Research involving cover crops is not always best suited to the small
plot design used on most university farms. Further, as it relates to cover crop
research specifically, the typical 3-year funding cycle common to many research
programs is not long enough to capture the cumulative impacts of a cover crop
system. The use of annual ryegrass as a
cover crop in fragipan soils is an example. While short-term benefits become
evident quickly, like erosion control and nitrogen recycling, the impacts of
ryegrass on fragipan soils are realized only over a longer timeframe; the
effect of annual ryegrass on fragipan becomes pronounced between the third and
fifth years, when corn crops show significant gains in rooting depth and
yield. So, funding a 3-year research
program might discount the true potential and lose out on some of the most remarkable
Given that the
cover crop revolution didn’t start on university farms, it’s more understandable
why some professors and Extension researchers were reluctant to sign on as early
cover crop advocates. In fact, some actively campaigned against annual ryegrass
because they feared the cover crop would create more headaches than benefits.
The reticence of
university researchers, however, did not deter farmers like Junior Upton (Springerton,
Illinois) and independent thinkers like Mike Plumer. Their on-farm discoveries of
annual ryegrass’ benefits in the mid-1990s won early support from Oregon ryegrass
seed growers as well as their Ryegrass Commission. A decade of replicated field
trials helped determine which annual ryegrass varieties were the most winter
hardy and which management practices were most effective for control of cover
crops with herbicides. The trials also attracted media attention and thus
increased university interest.
“Farmers change their
crop management practices only when the economic benefits can be demonstrated,”
said John, who has continued to farm his own acres as well. “Telling them about
soil health is secondary to economics. So, when they hear from their neighbor
or find out for themselves that cover crops can save you money or boost your
profits, they pay attention. Annual ryegrass does that by reducing erosion and
compaction, while boosting yields, improving water infiltration, and many other
So as Mike Plumer
retired, and passed away shortly thereafter, John has tried to continue some of
Mike’s projects and maintain relationships with many of his long-time
farmer/collaborators. “I like to think I’m
helping to keep the ball rolling,” he explained, “but it’ll take many more people
like me to move the ball as far down the field as Mike did. I’m just glad to make sure his efforts and
interests are continued, as we shared the same interests.”
Commission has hired John to further Plumer’s work, with Junior Upton and many
of the other growers Plumer attracted to cover crop usage. One of those happy
customers, Illinois farmer Marc Bremer, has been using annual ryegrass in rotation
between cash crops and grazing cattle for 15 years. On grazed pastures, he’s
seen corn yields increase to 230 bushels/acre and beans to 80 bu/ac. John’s research
will create data on the further reduction of fragipan on that farm over the
next five years, comparing grazed and un-grazed fields using annual ryegrass to
other acreage tilled in the old “conventional” way without cover crops.
In addition, John
will be following up with the University of Kentucky, as researcher Lloyd
Murdoch heads into retirement. John will further Murdoch’s work and provide
crucial location assistance to Dr. Claire Phillips, a scientist working with
USDA’s Agricultural Research Service in Ames, Iowa. “I’ll be monitoring their
test sites in southern Illinois,” John said, “including acreage owned by Junior
Upton.” “We’re placing field sensors to track hydrology in soils affected by
fragipan and gathering data on soils freed from compaction by using annual
ryegrass,” he explained.
is critical in our region and, really, in most parts of the world as well. Reducing runoff, soil erosion and related
nutrient loss is a major factor in the efficiency of our mostly unirrigated
row-cropping systems,” John added. “Employing annual ryegrass as a component of
cover crop programs helps to keep soil in place, improve water infiltration
rates and significantly increases the rooting depth limited by fragipan
soils. “This USDA-ARS led research has
national implications,” he said, “and will help to further quantify the impact
of annual ryegrass on fragipan soils and its relationship to the soil’s ability
to hold more available moisture.”
You’ve probably seen this motto: “Feed the Soil, Not Just the Plants!” Doing that helps the soil prosper, and then the crop health and grower’s prosperity grow accordingly. This motto may somewhat represent the tilt towards “regenerative” or “sustainable” agriculture globally.
In the old days, feeding the plant necessary nutrients may have been adequate. But doing that disregards the quality of the soil and, in the long run, impacts the growth of crops and the profitability of the farm.
Here’s a rough definition of soil health, taken from a document at Cornell University: …”the continued capacity of the soil to function as a vital living ecosystem that sustains plants, animals and humans (NRCS, 2012). Characteristics of a healthy soil include good soil tilth, sufficient rooting depth, good water storage and drainage, rich and diverse soil life, stored carbon and an adequate supply of nutrients.”
There are three overlapping elements involved in assessing soil health: its physical nature as well as its biological and chemical properties. Managing nutrients only amounts to paying attention to just one of the three component parts.
In the above graph (developed by Cornell University) you can see a hypothetical analysis of a farm, wherein the chemical elements are all in the “green” or “ok” realm, but the physical and biological aspects are suffering. This is typical of farm acreage that has been in continuous tillage and mono-cropping for decades. So, even with the chemical aspect getting a passing grade, the overall quality of the farm soil is only “medium.” Medium won’t ever give you the best performance.
As the chart shows, some of the aspects of the soil’s physical health include its water carrying capacity, or “infiltration”. It also looks at compaction at the surface and down to about typical plowing depth.
Among the soil properties under the “Biological” heading, the assessment looks at the amount of organic matter, the “Autoclaved Citrate Extractable (ACE) Protein. which indicates the amount of protein-like substances present in the organic matter, the soil’s respiration and the amount of active carbon.
Though it might occur to you that there would be a lot of expense to assessing your fields’ soil health to this extent, agronomists at Cornell would disagree. “Qualitative, on-farm, in-field assessment of soil health does not need to involve special analyses, only the informed observation and interpretation of soil characteristics. This is usually done by visual assessment, but the smell and feel of soil may also be involved. Field test kits for measuring several indicators are also available (e.g. NRCS soil quality test kit).“
The article goes on to say that, “While this approach is more subjective and therefore can reflect user bias, the results can be very informative in making management decisions when detailed guidelines and training have been provided.”
Finally, the article says that, “The health of a soil can change over time as a result of use and management, therefore it is crucial to measure soil improvement when implementing new or modifying current management practices.Climate change, particularly the impacts of CO2 and N2 O, can be mitigated through improved soil health management while at the same time building soil resilience.”
Cover crops are an integrated part of the solution, part of moving away from nutrient management to soil health management. See the following management suggestions, again provided by the Ag Sciences folks at Cornell University. For each “constraint” against soil health, there are corresponding short term and long term management suggestions.
Organic matter, a foundational element of health soil, is the key to plant health and consequently human health. Without organic matter, there would be nothing to feed the myriad forms of life that make up healthy soil.
Cultivation of land leads to extreme loss of organic matter. Midwest crop acreage 150 years ago probably had between 4 and 5 percent organic matter. Some acres today have less than 2 percent. Thankfully, with no-till and cover crops, a healthy percentage of organic matter can be regenerated in a decade of careful application of conservation practices including cover crops.
According to crop scientists like John Biernbaum at Michigan State, there are multiple types of organic matter. First, there is the living part which includes plant roots, earthworms and other insects, bacteria, fungi, protozoa, and more, Then there are several “dead” parts of organic matter in various stages of decay. Some forms, like plant leaves, stalks and roots, break down in a matter of weeks to months, while other forms like tree trunks, take decades or longer.
Organic matter, in addition to being the primary source of food for the many forms of life in the soil, is also important for the infiltration and retention of moisture. Researchers tell us that each pound of carbon in the soil can retain up to 40 lbs of water.
Cover crops function in a couple of important ways in this cycle. First, they keep the soil in place, preventing erosion. Next, the roots of cover crops exude sugars that feed life below the surface. Finally, they create channels through which rain and snowmelt get deeper into the soil profile.
When Hollywood and TV legend Woody Harrelson decides to spend his time and money promoting cover crops and other conservation methods, it’s a sure bet that America is embracing the idea of nurturing the soil from which our food comes.
The 2020 film Kiss the Earth was released last year and is available for streaming on Netflix and Vimeo. One of the “stars” in the film is Ray Archuleta, a career Conservation Agronomist with NRCS
Another documentary called Living Soil, with host Jerry Hatfield, goes into more detail about the components of healthy soil. Hatfield, director of the USDA’s National Lab for Agriculture and the Environment, is free to view on YouTube. https://www.youtube.com/watch?v=ntJouJhLM48
The hunch that annual ryegrass use was
breaking down the fragipan at Junior Upton’s farm in Illinois was like music to
Lloyd Murdock’s ears. The University of Kentucky (UK) research team had begun
to experiment with different chemicals in the greenhouse and field where he
worked at the University of Kentucky’s Princeton farm and in the lab on the
While they waited for results on field
plots of annual ryegrass they planted that year, the UK research team began
working with the plant in controlled lab and greenhouse environments. They
created extracts made from annual ryegrass roots, as well as from the foliage. “Naturally
cemented fragipan clods were placed in a solution of annual ryegrass extract.
Thirty days later the size and distribution of the remaining aggregates were
determined. As the binding agent in the fragipan is dissolved by the chemical,
the fragipan clod begins to fall apart. The greater the dissolution of the
binding agent, the smaller the remaining aggregates. Ag related chemicals were also tested but it
was annual ryegrass that demonstrated the most significant ability to dissolve
the cementing agents biding the fragipan particles,” he said.
Lloyd also made numerous trips to
visit Junior’s farm in those years, to authenticate what they were experiencing
there, and to apply what was being gleaned. “We’ve known, for example, that
some plants do not exert much pressure at the root tip. Annual ryegrass roots
tips, on the other hand, exert a high amount of pressure,” Lloyd said. “So
those roots will seek out a crack or weak spot in the fragipan and break through
there. It doesn’t take many roots getting through to make a difference. And
when corn roots follow those same channels the following year, they’re getting
access to nutrition and moisture below the fragipan,” he added. The combination
of plant chemistry and root pressure has a dramatic effect on fragipan.
The UK team did replicated trials in five Kentucky and
Indiana sites. Below, Table 1 shows, in controlled
studies, annual ryegrass reduced the thickness of fragipan significantly at
each site, allowing more soil depth for crops.
Dave Fischer is a beef producer from
Indiana, and it is his Debois County farm mentioned in the table above. Fisher has
planted annual ryegrass on his farm for the past eight years. “When I visited his
farm last year, I found that he had lowered the fragipan depth by 14 inches and
had annual ryegrass roots 29 inches deep,” Lloyd said.
“Those results floored me,” said Fisher in
a video on the project. “But at the same time, I
had noticed that these fields seemed to not dry out as fast compared to what
they used to and to neighboring fields. We were hanging in there a lot longer
during drought periods,” he said. “I would plant it just because of the forage,
but the addition of breaking up the fragipan has just been super.”
“I’m more excited about this research than any other project
I’ve worked on in my 45 years at the University of Kentucky,” Lloyd said in a University news article, “because it can help so many people. It is something that
farmers can work into their operations now to increase their yields.”
As he prepared to retire once again, Lloyd said he has been
grateful for the Oregon Commission, and others, whose support was crucial for the
UK team’s work on annual ryegrass research. “And it looks like others who have
noticed our work are picking up where we’ve left off,” he said with a smile.
“Claire Phillips, who received her PhD from Oregon State University and has
been a soil scientist for the USDA in Iowa for six years, as well as Dr. Dan
Olk and Dr. Dana Dinnes are interested in continuing the work we began. And,
likewise, John Pike, an agronomist at Southern Illinois University, has also
expressed interest in helping to further the research of fragipan and to
continue promoting the use of annual ryegrass as a cover crop.”
An “aha” moment began this 14-part
series, and it’s fitting we end it with another aha moment!
Dr. Lloyd Murdock has spent many of his productive years at the University of Kentucky as a soils and crop specialist. The link in the previous sentence summarizes a decades long effort that has earned Lloyd a well-deserved reputation as one of America’s “pioneers of no-till agriculture.”
“I had retired in 2012,” Lloyd
recalled, “but specifically returned part time the following year to focus research
on how to eliminate, or at least reduce, a deep layer of cemented soil called fragipan.
Of course, during his career, Lloyd was aware of the seemingly intractable
fragipan problem. “But with all the other things I was involved with, I didn’t
have enough time. So, when I returned in 2013, I involved a soil chemist, soil pedologist
and another agronomist and we set about doing lab, greenhouse and field testing
on how to break up that cemented layer.” The breakthrough project is described
in a lengthy report published last year by the University of Kentucky.
Fragipan soils are present in almost a
third of the US, running from east Texas northeast into New York and parts of
New England. In Kentucky alone, it hampers agriculture on 2.7 million acres. Fragipan
is almost like bedrock in places, beginning anywhere from 18 to 32 inches below
the soil surface. The layer becomes cement-like because of an iron-associated aluminosilicate
that binds soil together tightly and restricts water penetration and root
growth. Crops grown on these soils have limited soil depth, below which crop
roots cannot go. Furthermore, in wet weather, fragipan prevents proper
drainage. Topsoil gets saturated and squeezes out oxygen, increases the loss of
nitrogen, delays planting, and increases the chances of even more soil compaction
with any new tractor traffic.
In the 40 years he was researching and
teaching the benefits of no-till, Lloyd said he recalled how people were
addressing fragipan. “I was involved in early experiments injecting lime or
other chemicals into the pan on 30-inch centers, hoping to break it down,” he
said. “I was aware of field trials at other universities using deep mechanical
rippers to break up the fragipan. But in
a short time, the soil would reconfigure and harden once again. It was quite expensive
and none of it proved effective.”
Then in 2014, through the Oregon
Ryegrass Commission, Lloyd was introduced to Mike Plumer, another pioneer in
conservation agriculture who had been working on contract to the Commission
since the early 2000s. It was he who had begun to quantify the value of annual
ryegrass as a cover crop. Inadvertently, at Ralph “Junior” Upton’s farm in
southern Illinois, they stumbled on the discovery of annual ryegrass’ deep
roots. And in the process, they saw how ryegrass roots seemed to be growing
into the fragipan on Junior’s compacted acreage.
“Everything happened by accident,” Junior
said. “When I started, I only had about 5 inches of topsoil before I would hit
the fragipan. I was trying to get through dry weather. I got a grant and
started studying no-till and cover crops. Then a representative of Oregon
Ryegrass Commission asked me to try annual ryegrass as a cover crop.”
“They’d stumbled onto something really
big,” Lloyd said. “Thankfully, Mike and Junior kept good records on their
annual ryegrass work. They found that after a few years, the corn production on
the acres Junior planted annual ryegrass began to outproduce fields without it.
When they started tracking progress on those fields in the early 2000s, he and
Mike determined that Junior’s acreage was producing 10 to 20 bushels per acre
less than the average in that county. Today, those same acres are producing 40 bushels
per acre more than the county average.