Plant Cover Crops

Learning about the benefits of planting cover crops.

roots

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 Crops Enhance Water Infiltration/Percolation

In late September of 2011 I was walking in our family corn field in central Indiana–in the pouring rain. Following the wettest spring in the eastern corn belt in 100 years we had a summertime drought that saw less than 2 inches in July and August combined. In that same time period we had 32 days above 90 degrees.

We just had 3 inches of rain yet my soil was dry at 1/2 inch in this area that had been tilled wet in the spring.

On this September day we were having rain…3 inches worth of glorious rain! I threw on my rain coat and Tingley boots, grabbed my shovel and went into the corn field where our cover crop plots had been planted in the fall of 2010 and killed in May 2011. As I walked through the field I noticed that where the soil had been tilled (see previous blog post) I was seeing dry soil underneath my boot track! Now catch the scene here…no rain for much of 60+ straight days…now a 3″ rain and virtually none of the moisture getting into the soil! Literally I had less than 1/2″ of the soil depth that was moist! Dry footprints followed me all the way to the end of the field. I was not happy.

When I reached the area where the cover crop test plot was (that area was not tilled this spring) I dug into the check area that was no-tilled yet did not have a cover crop. In that area I dug into the soil and I found moisture 2 1/2-3 inches deep. This area was now no-tilled for 23 straight years. That made me feel better.

Water was standing (or running off) of the soil that was tilled wet in the spring of 2011. There was very little infiltration from a 3 inch rain

 

In this photo we see infiltration at 2 1/2 - 3 inches deep. This soil has been no-tilled for 23 straight years.

 

Then I dug in the area that had been no-tilled for 23 straight years and had a cover crop the previous winter. I was very pleased when I dug in the areas where we previously had annual ryegrass and cereal rye and found moisture had filtered (penetrated) in 7 (seven) inches deep!

Water infiltrated 7 inches deep where we had corn no-tilled into cover crop rye.

 

 

 

This section of the field had a cereal rye cover crop in 2010-11 and was no-tilled. Note the lack of water standing on top of the soil! Where did the water go? Into the soil!

 

Watch these videos on what I found when digging for earthworms in this sections with cover crops and no-till and where there was tillage without a cover crop. I believe we have an additional answer to why I had so much better infiltration where I had the cover crops..earthworms and roots!

This "rogue" radish provided information that we had a compaction zone at about 3 inches deep in our no-till field; thus reducing water infiltration where we had no cover crop.

Yet, I wondered, why did the moisture stop at 2 1/2-3″ in the no-till plots? I found the answer from a rogue radish. We had a few radishes that came up in the field that had been planted in the fall of 2010 (the fall of 2010 was so dry that many of the radishes did not come up until very late…or not until spring, or in a few cases until mid-summer).  As I previously wrote, Radish does have some hard seed.  I dug around one of the radishes and found a constriction in the radish at 2 1/2-3″ deep! Even after 23 years of no-till I still had a compaction problem! I believe that is one reason why cover crops help producers to transition from conventional tillage to no-till…cover crops penetrate through compaction layers.

66″ No-Till Corn Roots Following Cover Crops

This is not a scene from a horror flick...it's a scene from Frank Gibb's experiment showing that smoke was coming up from the tile drains over 200 feet from the tile entry point.

I had a “see it to believe it” moment in late August near Stryker, Ohio (Williams County – NW Ohio).  A very long and deep root pit had been dug as Frank Gibbs (Ohio NRCS Resource Soil Scientist) was looking for the tile in a continuous no-till corn field.  I’m thankful that the tile was not easily found because we found pretty remarkable “things” going on in the soil beneath the soil.  What were those “things” we found?

Watch the Frank Gibbs video to see how special cover crops and no-till make a tough soil a healthy soil!  Frank does some pretty incredible work that shows the value of having a healthy soil.  Now, watch this second video of the smoke test results.  I have seen this test three times and NEVER seen it this awesome!

  • corn roots and earthworm channels up to 5 1/2 feet deep on no-till corn
  • top soil approximately 3 feet deep on top of lake bed soil
  • smoke from Frank’s “smoke test” coming up from 34″ deep over 200 feet away from the entry point

Frank says in the video that often times that the corn roots would “be turning out” when they hit the lake bed soil.  But because of cover crops and no-till the earthworms had plenty to eat for much of the year and the soil was very healthy compared to similar soil types in NW Ohio.  Obviously these roots did not “turn out”…they kept going down all the way to over 5 feet deep!

 

Annual Ryegrass Roots Video – 40″ deep in 2 1/2 months!

I was in western Pulaski County of Indiana again yesterday afternoon (11/16/2010) at the Leman farm. This is the third year that the Leman’s have used cover crops. Curt Leman dug some pits for us so we could see what kind of rooting depth we have achieved since the annual ryegrass was planted on Sept 4, 2010. When I got in the pit I was very pleasantly surprised! I found ryegrass roots that are already 40″ deep! Watch the video to see what other goodies I found!

After digging out the section of soil that had the dark band we found that we actually had corn roots from the 2010 crop that were at least 36″ deep. My friend from Michigan who is a “corn guru” tells me that in most soils in most years that corn roots go 18″ deep…so we gained approximately 18″ greater depth of corn roots by using annual ryegrass for one year…impressive isn’t it!?! And, we didn’t dig deeper than 40″ so possibly the roots went deeper than that. I believe that helps explain our improved corn health and yield where we had ARg as a cover crop vs where we had no cover crop (again, see previous post).

In the photo you see the dark band of soil found at the 30-36″ soil depth. The following video reveals what I could not see when in the pit…

I anticipate we will dig in the spring at the Leman farm again. What we found after 10 weeks was literally amazing!