Plant Cover Crops

Learning about the benefits of planting cover crops.

Cover Crops in the upper Midwest

Fall Cover Crop Management

While in southern Minnesota in early September 2013 I was asked when a farmer should plow his cover crop field this fall because he needs the fields to be “black” this winter in preparation for next spring.  I shuddered.  There I was in a beautiful field of cover crops that are jump-starting some biology on a “biologically dead” field and the farmer wants to kill his biology driving mechanism.  UG!  The main reason he wanted to till the field was to have warmer soils in the spring where he had black soil.  I shared that our research sowed much different results.  His thought process sound right but has proven to be a myth, not a fact.

A beautiful stand of Oats, Berseem Clover, and Pasja Hybrid Brassica on prevent plant acres in SO. MN
A beautiful stand of Oats, Berseem Clover, and Pasja Hybrid Brassica on prevent plant acres in SO. MN

I told the farmer to leave the cover crops in all winter and use conservation tillage next spring.  (He’s not a no-tiller.)  We dug some shallow root pits for a field day and we found many problems that I believe can be somewhat rectified if the cover crops are left in all winter.

We found many soil health problems in this prevent plant field

  • Severe compaction– many areas had compaction starting at 2-3″ deep.  Part of that was from spring tillage of wet soils…but the compaction was about 8″ thick as the soil was coming up in blocks the size of cinder blocks!
  • Lack of soil biology – I know this because we found a significant amount of corn fodder 2 foot deep that was not even breaking down.  It would have been buried with the deep ripper 18 months ago.  I could not believe my eyes!
  • Lack of aeration in the soil – the soil was literally rock hard.  We did find a few earthworm channels but it was so dry that worms were small and deep.
  • Low organic matter – I’m not sure how low it was but there was very little soil structure.  I talked with a regional NRCS employee and the local SWCD specialist and both men lamented that many of the soils in that region were “about as bad as this one”.
We found corn fodder two feet deep that had not yet decompose after over 18 months.
We found corn fodder two feet deep that had not yet decompose after over 18 months.

I need to be fair.  The farmer currently renting this field has only farmed it a few years and he is making major strides to improve this farm.  But he has lots to accomplish before he has a healthy field.  Having cover crops are a great first step and he knows it.

Other solutions (instead of cover crops) being proposed to fix the “tight” soils (“unhealthy” soils) in the region

  • Tile – LOTS and LOTS of tile has been installed in prevent plant acres this year.  Farmers know they need aeration and percolation in their “tight” soils.  The regional specialist from NRCS lamented that many farmers don’t believe that cover crops are a solution to make their soils better long term.  Tile is not bad; but tile and cover crops are a much better solution.
  • Deep ripping – this will get air into the soil and break up compaction, but will it build soil health?  No, it will not  (note the corn fodder found 2 foot deep in a root pit).  Let cover crops naturally deep rip the soil.
  • Tillage- and lots of it – many fields in the area had been tilled (disked, field cultivated, etc…) four times already to control weeds…Unfortunately it also reduces organic matter and soil structure and soil health.

So what should happen with the cover crops heading into winter?

  • Leave the cover crop growing into the winter – This will give the best opportunity to help with aeration and percolation.  This also helps build soil structure and reduce compaction.  (See deep ripping, and tiling above…just let the cover crops do this naturally!)
  • Sarah Carlson from Practical Farmers of Iowa recently wrote an article about this topic and you can find it here Prevent Plant, Cover Crops, Now What 2013.
  • Let the cover crops keep putting down deep roots – we found roots of crimson clover, radishes, cereal rye, annual ryegrass, oats, and Pasja all around 24″ deep.  Let them keep growing deeper to open up the soil to get air and moisture deeply into the soil profile.
This 5 week old PileDriver Radish shows the compaction zone starts at around 2-3" seep. Roots on this radish went over 24" deep despite very dry conditions.
This 5 week old PileDriver Radish shows the compaction zone starts at around 2-3″ seep. Roots on this radish went over 24″ deep despite very dry conditions.
This field had very poor soil structure. The regional NRCS specialist told me that many fields in the area had similar issues
This field had very poor soil structure. The regional NRCS specialist told me that many fields in the area had similar issues

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!