Plant Cover Crops

Learning about the benefits of planting cover crops.

Radishes

Cover Crop Field Day Set in Blooming Prairie, MN

PileDriver at Hagan Farms 2 33 days
This Radish was planted in late July 2013 and after 33 days has tremendous growth. This mix included oats and crimson clover and radishes.

Cover Crops will be the main topic of discussion on September 4, 2013 at a cover crop field day and meeting in Blooming Prairie, MN. I have the privilege of speaking at this event as we look at cover crops on prevented plant acres.  We will also look at what cover crops work best in the upper Midwest.  We will be on Brad Hagan’s family farm and possibly look at Dale Ramsey’s farm too.  Please note that we will be looking in root pits (where the action really is)!

I received this note from Legacy Seeds representative Andrew Heath about the field day/meeting:

“We  plan on structuring the event much like an open house with designated times where you will be able to address the crowd. We will start the event at 10 am and have you speak from 11 to 11:45 and again at 1 to 1:45. There will also be transportation to the cover crop plot and some of the field that you, TJ, Brad and I visited earlier with root pits dug. This will happen from 12 to 1 and 2 to 3.”

I have seen the plots and have added photos here on this post to entice you to come if you are in the region.

As a side note, Hagan farms will be no-tilling corn into these fields in 2014.  We’ll follow-up on these fields next spring and see how these fields compare to others that did not have a cover on them.

This prevent plant field had plenty of nitrogen from manure to capture. Hagan farms used a hybrid brassica and spring barley to secure the nitrogen and Berseem clover to produce more N and provide better soil health.
This prevent plant field had plenty of nitrogen from manure to capture. Hagan farms used a hybrid brassica and spring barley to secure the nitrogen and Berseem clover to produce more N and provide better soil health.

Cover Crops to the Rescue!

A Huge Problem

Brad, TJ, and Andrew inspecting on of Brads many cover crop fields that were planted in July 2013.on prevented planting acres.
Brad, TJ, and Andrew inspecting one of Brads many cover crop fields that were planted in July 2013 on prevented planting acres.

Recently I was in Minnesota with Brad Hagen, T.J. Kartes, and Andrew Heath looking at Brad’s 1,000+ acres or cover crops.  Brad had not intended on planting any of theses acres to cover crops in July, 2013…his intentions were to plant them in August or early September.  But spring 2013 rains and floods kept Brad from planting corn or soybeans on most of his 1,700 acres near Ellendale, MN (about an hour SW of Rochester, MN ).  Brad attended a cover crop meeting TJ set up for me to speak at on behalf of Legacy Seeds last March and as I spoke I could see Brad’s mind working.  When the spring rains came so did phone calls from Brad to TJ and from TJ to Andrew or me (or both)…”what can I do to build soil during this disaster?” was the theme of the weekly (if not daily) phone conversations.

You can seemingly look for miles without seeing a cash crop planted in some areas of SE Minnesota
You can seemingly look for miles without seeing a cash crop planted in some areas of SE Minnesota

Cover Crops to the Rescue!

Brad’s goals are to build soil and to scavenge nitrogen from his hog operation and build nitrogen with legumes.  Realizing that we would plant in early-mid July and not in mid-late August we all understood that we did not want to have to mow to remove seed heads if at all possible – so we left Radishes out of the mix.  We also realized that we wanted to use a “summer” clover, so we used Berseem Clover for it’s excellent growth and N producing ability.  We chose Oats as the grass in most fields and then we added a twist, Pasja or Vivant Hybrid Brassica.  I have worked with Pasja for over 10 years and rarely ever saw it produce a seed head in the summer or fall.  While Pasja (nor Vivant) have a big tuber like a Radish they do have the ability to scavenge a tremendous amount of nitrogen and earthworms dwell around their roots.

Brad Hagen looking at his Pasja Hybrid Brassica and Berseem clover. These are brand new species to Brad.
Brad Hagen looking at his Pasja Hybrid Brassica and Berseem clover. These are brand new species to Brad.  This field was planted 10 days before the photo was taken.

In some later July (and soon to be mid-August) planted fields we chose to use Spring Barley and Crimson Clover along with PileDriver Radishes and Appin Turnips.  TJ and Brad requested this mix so we’d get later fall growth, deeper penetration through compacted soils (Radish vs. Pasja/Vivant) and excellent N production from the Crimson clover.  Spring Barley was available and many folks in Kentucky have told me that barley makes the soil “sweet” (whatever that means).  From experience I know that soil after Barley is quite mellow.

Early August Report

From what I saw on August 1 I was very impressed!  As other folks in the region were planting straight Oats or possibly a few were adding Radishes very few other folks seemed to totally share Brad’s goals.  Brad told me that he is doing these cover crops because he wants to build his soil and because he wants his 7 year old son to have better soil to farm when he grows up and farms his place like Brad does with his father.  I’ll have more photos in a month or so.  I believe Andrew, Brad and TJ will plan a field day for September.  It’s beautiful country near the Hagen farm…it probably will be worth the drive in September to meet Brad and his family.  They’re pretty special folks…

Take a look at my You Tube channel “covercropdave” to watch an interview I have with Brad and TJ.

This beautiful stand of cover crops was planted July 2, 2013 at Brad's dad's place not far from the hog barns. If you sniff this photo real hard you can smell the hogs!
This beautiful stand of cover crops was planted July 2, 2013 at Brad’s dad’s place not far from the hog barns. If you sniff this photo real hard you can smell the hogs!

 

 

 

Cover Crops and Prevented Planting Guidelines

There are thousands upon Thousands of acres - mainly in the upper Midwest not planted in early June 2013.
There are thousands upon thousands of acres – mainly in the upper Midwest still not planted in early June 2013.

Over the past few weeks I have heard from countless farmers in Wisconsin, Minnesota, Illinois, Missouri, Michigan, and Iowa that are considering taking prevented planting on all or parts of their farms. Growers Edge just published an excellent piece Prevented Planting Guidelines. 

Also see my articles on Prevented Planting Row Crop Acres – Which Cover Crops Can Help? and Summer Annual Grasses for Cover Crops for Prevented Planting Acres that may also be helpful.

Can Cover Crops Become Weeds?

In a previous post I wrote that cover crops can suppress weeds.  And many farmers are planting them with that primary benefit in mind.

But, can cover crops become weeds?

Unfortunately, the answer is “yes, they can.”  Obviously we never want this to happen on our farm.  And with good management practices, we can lessen the possibility that it will.

Two species that require precise management are annual ryegrass and radishes. Both annual ryegrass  and radishes benefit the soil tremendously and have been shown to increase profit per acre, but both must be carefully managed as well. Specifically, there must be a comprehensive plan for terminating annual ryegrass. If you are not absolutely clear on how you are going to do this, you should not plant it. Likewise, with cover crop radishes, you need to be absolutely clear on what you are buying and when the seed should be planted.

It only takes a few annual ryegrass plants that produce seed to create a weed problem - especially if wheat is in the rotation.
It only takes a few annual ryegrass plants that produce seed to create a weed problem – especially if wheat is in the rotation.

This is why Hans Kok, from the Indiana Conservation Cropping Systems Initiative often tells farmers that are trying cover crops for the first time to start with a few acres of oats and radishes as a cover crop.  His thinking is that because both oats and radishes die over the winter that farmers will not have to worry about terminating the cover crop in the spring.  And I agree with Hans on this.

However, cover crops are becoming more popular and many producers are convinced that they are excellent at killing weeds and cover crops.  While Ag Chemical companies have shied away from making too many recommendations on killing cover crops, farmers are confident in their abilities to “figure it out” and make cover crops work on their farm.  Why use “boring” oats and radish?  Let’s use Annual Ryegrass!

Don’t get me wrong, Annual Ryegrass is a fabulous cover crop with tremendous value as a cover crop and forage.  But, it does take more management than many other cover crops.  Annual Ryegrass provides high reward with some additional risk.  On our home farm we sprayed our soybeans three times to make sure all annual ryegrass was killed.

Planting Radishes too early or planting the wrong Radish can create a problem with seed production on the radishes...and you don't want that!
Planting Radishes too early or planting the wrong Radish can create a problem with seed production on the radishes…and you don’t want that!

I’d love to hear your “formula” for annual ryegrass control. Have you noticed any difference with terminating annual ryegrass on different soil types? Different temperatures? Different additives? Different times of the day?

 

Fertilizing Cover Crops & Planting Legumes After Soybeans

If you spend any time at all in cover crop meetings, you may have heard that it’s a good idea to add 20-50# of Nitrogen per acre to your cover crop – if you don’t have a legume in the mix or you don’t have manure available. You also probably heard (or participated in) the grumbling that predictably starts from the crowd. Who wants to fertilize a crop that they will not harvest?

While it’s true that producers will not “harvest” the cover crops, they will have healthier cover crops which should lead to healthier soils and healthier profits.

Manure as the No-Brainer

Obviously if manure is available it is a smart move to put manure where you will have or already have cover crops.  We know from research that cover crops can hold as much as 90% of the nutrients from manure applications.

We have also know that where manure is applied without a cover crop being present (even if worked in) we can lose a significant amount of nutrients into ground water or as surface run-off.

What About Adding Commercial Fertilizer?

The Radishes on the left had manure applied and those on the right did not have any additional nitrogen applied.
The Radishes on the left had manure applied and those on the right did not have any additional nitrogen applied.

But, what if there is no manure to apply and for some reason you do not want to include a legume in your system?

Is it worth applying 50# of nitrogen to produce a cover crop?

Let’s look at what we think we know:

  • Pages 22-24 of Managing Cover Crops Profitably provide formulas to figure out the value of using cover crops as a green manure in a cover crop system –  whether with legumes, manure, or fertilized.

Look especially at the section on “Potential losses” to see that there can be nitrogen losses even in this scenario.

  • Cover crop experts say to count on 50% of the N captured or N produced by a cover crop to be available to the next cash crop.
  • It appears that adding a grass with legumes or brassicas will help “slow down” the release of the N in the spring making it more slowly released to the next crop.

 

Here is a photo of the Ingham County Michigan Cover Crop Plot. Where there was a legume in the mixture there was considerably more growth and earthworm activity
Here is a photo of the Ingham County Michigan Cover Crop Plot. Where there was a legume in the mixture there was considerably more growth and earthworm activity

What can we expect if we plant a cover crop and we don’t add more nitrogen?

How will that cover crop do?

I will utilize work that Dan Hudson did when he was an Extension educator in Ingham County Michigan in cover crop plots he planted back three or four years ago.

  • Radish tubers are considerably smaller and the roots appear to not be as deep  (I have not dug a root pit in this scenario).
  • Grasses have a more shallow root system in forage settings when fertility is lacking.
  • The cover crops were pale green.
  • The “hungry” grass cover crops had less earthworm activity than in the grass + legume mix plots.
  • “Hungry” radishes and turnips had much less tuber and top growth, thus sequestering less nutrients (one of their main functions).
  • Winterhardiness on cover crops is potentially not as good when the cover crop is undernourished.

What can we expect after soybeans?

Do we need a legume in the cover crop mix following the beans or is having a grass and/or brassica to sequester the N from the soybeans good enough?

Let’s investigate the difference between adding a legume to a cover crop mix following soybeans compared to planting scavengers only.  The charts are from our family farm trials.  The charts show the chlorophyll readings of the corn in the year following the soybeans (and then following a cover crop).

It is important to look at the “Y” axis as each chart is slightly different in how it shows the top reading.

When Austrian Winter Peas were added to a scavenger (Radishes) the chlorophyll readings were very favorable compared to the no cover crop check plot and plots with just scavengers.
When Austrian Winter Peas were added to a scavenger (Radishes) the chlorophyll readings were very favorable compared to the no cover crop check plot and plots with just scavengers.
Just like the peas gave us an advantage over the no cover crop check the crimson clover showed very favorably.
Just like the peas gave us an advantage over the no cover crop check  and scavengers, the crimson clover also showed very favorably.

 

While the Oats and Radish showed exceptionally favorable in the early part of the season the plot are "ran out of gas" as the corn was pollinating.
While the Oats and Radish showed exceptionally favorable in the early part of the season the plot “ran out of gas” as the season progressed.
Straight Winter Cereal Rye was impressive early season but also did not fare as well against the check as the mixes with legumes
Straight Winter Cereal Rye was impressive early season but also did not fare as well against the check as the mixes with legumes.

As we looked at the yield of the corn in these plots we saw a considerable difference – suggesting that even after soybeans we might want to add a legume to improve the corn yield the following year.

Yields from the different cover crop plots shown above were:

Check Plot                                    105.24 bu/ac

Winter Cereal Rye                      126.86 bu/ac

Oats and Radish                          138.79 bu/ac

Crimson Clover + Radish           153.99 bu/ac

AW Peas + Radish                        164.82 bu/ac

Conclusion

All indicators seem to point that adding manure, a legume, or additional N might very well pay off when planting a cover crop, even after soybeans.  However, adding a nitrogen source is not necessarily vital to having a successful cover crop system.  I would suggest that you try different scenarios on your own farm and in your own system and see what works best for you.

Cover Crops and Bears?

Radishes, Crimson Clover, and Bears

Walking in cover crop fields in northern Indiana is easy compared to doing it northern Wisconsin.

In northern Indiana my main issue is tripping over large radish tubers sticking out of the ground.

In northern Wisconsin my main issue was that plus watching out for bears. I’m not talking about the Chicago Bears…but real live black bears!  Although I did not see any while conducting cover crop field days near Coleman, WI on October 18, 2012, hearing the stories about the bears raising havoc while AgVentures Co-op employees were harvesting corn plots made me quite nervous.

The cover crop plot was fabulous. There were 5 different mixes to observe plus straight radishes planted at 8#/acre.  The cooperator plans on taking yield tests over each different cover crop mix in his 2013 corn crop.  If he is able to do that I’ll keep you informed of the results.

This cover crop plot near Coleman, WI had beautiful radishes with large tubers – and thankfully NO bears!

 

 

 

 

 

 

 

 

 

 

 

 

The radishes were from 1″ to 3″ in diameter and quite deeply rooted. There was manure applied after wheat harvest so the radishes were “well fed”.

 

 

 

Terminating Cover Crops – Use Residual Herbicide

Terminating cover crops is part of the “stepped-up management” that using cover crops requires.  Over the past month I shot videos about killing annual ryegrass, killing crimson clover, and about the difference of killing cereal rye and annual ryegrass.  In each of the videos I examined the importance of killing the cover crop…and killing it dead.  Overall, most of the cover crop fields that I have seen had a very good burn down.  In more than a couple of instances it was obvious that the applicator missed a few (if not many) spots or strips.

Terminating Cover Crop Radishes

In the cover crop plots where Radishes were in the mix we now have plenty of Radishes in the corn!

But burndown is not all that we need to be concerned about.  In 2011 I saw photos from fields in Michigan that almost made my heart stop!

A corn field in southern Michigan had radishes that were taller than the knee high corn. And a field of soybeans had large radishes in it at harvest time.  Thankfully the corn field yield was not affected, but areas of the soybean field could not be be harvested.  At $12-13/bu soybeans that was an expensive lesson.

Applying glyphosate once a season without using a residual herbicide does not provide adequate weed control. These radishes germinated after the spring glyphosate application.

So how did these situations happen?  In both instances the producers used glyphosate for their burndown and did not  use (or had not yet used) residual herbicide.  Of course the radishes were not the only “weed” in the field, but it was the focus of the growers!

Terminating Cover Crops at Robison Farms

At Robison Farms in Central Indiana we have two issues going on in our fields this spring of 2012:

#1) Radishes are coming in the corn and soybeans, even though we did apply a residual herbicide!

#2) There are more annual ryegrass escapes than I’d ever like to see. We actually had very good burndown and we used residual herbicide too.  Note that these are NOT the only “weeds” that we have growing in the fields.  I cannot remember a year when we’ve seen so many winter annuals and broadleaf weeds survive residual herbicide.

My brother Don has been scouting our fields and he reports seeing ragweed, morning glory, cocklebur, Queen Anne’s lace,  and a variety of other broadleaf weeds across our 300 plus acres.  The weeds aren’t thick, but there are too many of them. So we’ve concluded that it is not “just the cover crops” that are escaping.

So what is the advice here?  Make a commitment to scout your fields for weeds, whether they be “cover crop species escapes” or other weed pressure.

  • Excellent weed control is vital for top profits in cash crops.
  • Use residual herbicide in corn and soybean fields.
  • Scout fields looking for escapes and other weed issues.
  • Terminate all escapes before they produce viable seed.
  • Realize that cover crop radishes do have hard seed and you most certainly will see radishes in the spring.
  • Oilseed crops (brassicas like radishes, turnips, rape, canola, kale, mustards) can stay viable in the soil for years. Scout each year in fields where you have had these brassicas.
  • Scout for brassicas later in the season as well.  This should not be an issue but don’t take a risk of losing acres of soybeans.  The soybean field in Michigan had no residual herbicide applied but the radishes that caused the problems came up later in the season (probably late July or early August gauging from their size at harvest).
  • In some years like 2012 (even if you did not use cover crops), you will have more weed pressure than other years.  Eliminating all weed pressure is important!
The casual drive-by look at this plot looks like we achieved a great kill on this annual ryegrass cover crop. The corn looks great, the grass looks brown and dead, but...
...in more than one area I found annual ryegrass "escapes" that are heading out or nearly heading out. These plants need to be sprayed right away so they will not produce viable seed.

 

Cover Crop Root Pits Reveal Plenty

During the first week of April I was in several root pits in northwest Indiana and boy did we find plenty of interesting factoids! I was assisted by Eileen Kladivko from Purdue University on one day and Barry Fisher, Indiana NRCS State Agronomist, on another day.

What We Found in the Cover Crop Root Pits

We found several night crawlers and smaller worms as well in each pit we were in
  • Earthworms galore, especially where we had radishes and/or crimson clover. But the earthworms were plentiful in all cover crop species.
  • Earthworm channels 48″ deep in a field that had been long term no-till with one year of cover crop annual ryegrass/radish mix (planted after soybeans).
  • Roots from two different  crops in the same root zone/earthworm channel (soybeans and cover crop roots) over 30″ deep.
  • Earthworm eggs where radishes had decayed.
  • Soybean nodules 26″ deep on roots that went 44″ deep (long term no-till field – 10 years).
  • Annual ryegrass roots that were not as deep following corn as they were following soybeans (less N available for them to grow as vigorously).
  • Canola or oilseed rape in fields where bin run oats had been planted instead of seed oats.
  • Continued evidence of compaction. One year of cover crops does not eliminate all compaction issues (though roots from cover crops did penetrate through the compaction).
  • Radish and radish roots that were 34″ deep last fall were found at 40″ deep this spring (though dead).
  • Living radishes. Several radishes survived the Indiana winter (very mild winter), especially where they were protected by crimson clover and annual ryegrass.
  • 20 earthworm channels and 5 earthworms in an area 8″ by 8″ square at 6 inches deep (in a mixture of annual ryegrass, crimson clover, and cover crop radishes).
  • 700 acres of oats and radishes looking very different in the spring than it did in the fall!  (Click the links to see the different videos)

Miscellaneous Notes from the Cover Crop Root Pits

The farmer from our first cover crop root pit dig on April 4th reported that he saw less visible drought stress where they had long term no-till and cover crops, attributing the healthier plants to increased root depth.

We saw several fields of cereal rye after corn stalks being grazed by beef cattle.

Barry Fisher encouraged everyone to “expand your farm vertically.” In other words, don’t just keep buying/renting more land. Instead, put cover crop roots down deeper to create better land where you farm – and get more yield.

Be sure to control your annual ryegrass instead of waiting on the crimson clover to grow taller.  Much of the ryegrass was 10-12″ tall with the crimson clover at 6-8″ tall.

Farmers are becoming more creative with cover crop applications and types, and they are finding success – not surprising!

 

Other than the "extra goodies" from the VNS oats, this field was ready to plant without herbicide in the spring.
We saw several fields where cattle were grazing cereal rye planted into corn stalks.
Cereal rye in one row and crimson clover and Appin turnips in the other row (mixed together).

 

One of the joys of working with farmers is the excitement I see on their faces when they "get it" about soil health. There were several excited farmers again this spring.
We found several earthworm eggs around the decayed radish holes.
We found roots from soybeans and annual ryegrass in the same root zone/earthworm channel.

Cover Crop Field Day Set at Robison Farms

CISCO Seeds, Robison Farms, and Dougherty Fertilizer are sponsoring a Cover Crop Field Day and Root Dig at the Greenwood, Indiana farm. If you’ve not had an opportunity to see cover crops in a real life farm setting, this will be a great meeting for you . There will be multiple species available to look at and expert agronomists on hand to answer questions.

 

When:

Wednesday, November 30, 2011 from 2-4 P.M.

Location:

Corner of Five Point Road (300 East) and Main Street (Rocklane Road) east of Greenwood, IN

Contact:

If you have questions or need further information contact  Don Robison at donrobison@ciscoseeds.com or 317-357-7013

  • Rain or shine we will have a gathering (call if the weather is bad for “plan B”)

 

Cover Crop Field Day Highlights

Come see ten different mixes and/or species of cover crops in a large plot setting.
  • 1100’ lineal feet of cover crop plots
  • 10 different mixes or straight species shown
  • guaranteed weather! (not saying what kind)
  • working with NRCS, SWCD, and Dougherty Fertilizer
  • root digs (weather contingent)
  • Cover Crop Agronomists on hand for tours and Q/A sessions
  • See over 150 acres of various Cover Crops withing 1/2 mile of plots

 

Purpose of the cover crop field day

To see different species of cover crops in a real to life situation. This was a soybean field that had the cover crops applied over the top of the standing crop at roughly 50% leaf drop.

 

Species You Will See

 

  • Radishes
  • Turnips
  • Crimson Clover
  • Oats
  • Winter Rye
  • Annual Ryegrass
  • Austrian Winter Peas
  • Several Mixes including the above species

 

 

 

Directions:

From Indianapolis

  • Take I-65 South to Exit 99. Turn Left at end of ramp and travel 1.5 miles east to the plots

From Louisville

  • Take I-65 North to Exit 99. Turn Right at end of ramp and travel 1.5 miles east to the plots

From Columbus, OH

  • Take I-70 West to Indianapolis, follow 465 South to I-65 South to Exit 99. Turn Left at end of ramp and travel 1.5 miles east to the plots

From Terre Haute

  • Take I-70 East to Indianapolis, follow 465 South to I-65 South to Exit 99. Turn Left at end of ramp and travel 1.5 miles east to the plots

 

Just down the road we plan on digging another pit where Annual Ryegrass and Appin Turnips were applied after hog manure was knifed in after wheat.

Cover Crops underground…I was not disappointed, I was a bit surprised!

The Crimson clover had dense roots and we found a number of them at over 40″ deep.

At cover crop field days over the past few weeks many interesting aspects of cover crops were revealed. 

One reminder about cover crops; it is NOT what is above ground that is the best indicator of success. 

Please take a shovel with you when you evaluate cover crops and dig up some roots so you get the real story.

The radish tops were still quite eveident and some of the holes had yet to fill in completely. This field at Four L Farms had tremendous growth from the radishes and crimson clover last fall. The clover survived the winter beautifully.

First, we found deep roots from multiple species. While we expect to find deep roots from annual ryegrass we continue to be amazed at how deep other species are penetrating.  At Four L Farms near Francesville, IN we may have set a “world record” by finding 40+” deep roots from crimson clover.  We also found cover crop radish roots 40″ deep and annual ryegrass roots 54″ deep (as deep as the pit was dug).

When the pit walls collapsed I was quite surprised to see many root channels deep into the soil. I had never seen anything quite like this!

 

 

 

 

 

 

 

 

 

Next, we found earthworms in some fields and not in others. I think that this was a function of soil temperature and moisture.  (The soil temperature averaged 47 degrees at a 4″ depth).  However, I’m not sure that is correct.  We found a pretty good number of worms where we had more manure applied at Four L Farms on the annual ryegrass.  Typically crimson clover and radishes will have more earthworms around their roots than annual ryegrass…but this spring that was not entirely the case.  While we found worms around the radishes we found less than I expected around the crimson clover roots (again, no manure was applied in that field).

I always get a rush of excitement when we start digging pits so we can see what God did over the winter with our cover crops!

In the fields in Lake County, Indiana we were looking at fields that had never had cover crops in them before.  The producer is following corn and going to soybeans on most of the 900 acres he had flown on.  The mixture of cereal rye, annual ryegrass, and GroundHog Radish has looked good since last fall.  We were pleasantly surprised by what we saw there.  Nearly 20 producers came to the field day and saw root channels along the side walls of the pit.  Actually the pit collapsed and revealed an awesome display of root channels like I had never seen before.

I probably enjoy looking at cover crops way too much.  With the response from the producers looking at the root pits, I think most of them are getting excited too.