Plant Cover Crops

Learning about the benefits of planting cover crops.

Austrian Winter Peas

Prevented Planting Row Crop Acres – Which Cover Crops Can Help?

The following was originally posted on May 27, 2011 when the Eastern Corn Belt was suffering with severe flooding and wet conditions.  In 2013 the Upper Midwest – especially Iowa, Minnesota, and Wisconsin – is flooded and wet.  Many farmers are considering taking the crop insurance for prevented planting.  Even if it would stop raining – which does not appear will happen anytime soon – many farmers will not be in their fields for two weeks.  While locations are different, the recommendations below still apply.  Please keep the farmers in the Upper Midwest in your prayers; they need it!

For other options that might include growing cover crops for forages click here.

More rain tonight on already flooded fields create a tough situation for many Midwestern farmers.
More rain tonight on already flooded fields create a tough situation for many Midwestern farmers.

In 2010 there were wet spots in fields that were never planted,  so some ingenious farmers planted cover crops in those spots after they dried out.  Now in 2011 there are several entire fields that may not be planted to cash crops at all.  I have heard from two friends in Ohio that are working on plans to help northwest Ohio farmers know what to use on their prevented acres.

Maybe this is not an issue where you live.  I hope you never have to face a spring like this year in the Eastern Corn Belt, where many producers in Ohio, Indiana, Illinois, and Michigan are struggling to get their crops in the ground.  The forecast is for many more days of rain to finish out the month of May.

For wet spots in fields there are many good options like these cover crop radishes that were planted later in the season in a field of sweet corn.

For prevented planting the cover crops may not be harvested until after November 1st.

So what are the options for planting cover crops in the prevented planted fields?  Below I will list the options with a few of their benefits and also some disadvantages.

Oats

Advantages

  1. Provides erosion control
  2. Scavenges nitrogen
  3. Grows a deep and fibrous root mass
  4. Promotes mycorrhiza growth
  5. Quick to establish
  6. Relatively inexpensive
  7. Can be broadcast and lightly tilled in
  8. Can be added to other cover crops to add additional value
  9. Can spray with broadleaf herbicides if necessary to control weeds

Disadvantages

  1. While they provide cover and decent root growth they do not provide additional nitrogen to the soil (at the most it would be very minimal)
  2. Best to use seed oats vs. bin run oats for optimum value
  3. If planting wheat after oats there may be some “grass after grass” issues (I’m not confident this will be a problem and would welcome comments)

 

Field Peas or Austrian Winter Peas

Austrian Winter Peas and cover crop radishes were planted into prevented planting acres in Michigan in 2010. These peas were producing nitrogen for the 2011 crop while fields that were sprayed or tilled for weed control had no such benefit.

Advantages

  1. Can provide 60-120 # nitrogen/acre (excellent if following with wheat in the fall)
  2. Can be broadcast and lightly tilled in (1″ or deeper)
  3. Can be added to other cover crops to add additional value (add to oats)
  4. Can spray with broadleaf herbicides if necessary to control weeds

Disadvantages

  1. Slower to establish than oats
  2. More costly than straight oats
  3. Seed MUST be inoculated at the time of planting

 

Crimson Clover

Advantages

  1. Can produce up to 150# N/acre within 100 days (great option if following with fall planted wheat or Winter Barley)
  2. Fairly quick to establish
  3. Relatively inexpensive
  4. Can be broadcast and lightly tilled in (1/4-1/2 inch deep)
  5. Can be added to other cover crops to add additional value (add oats at 1 bu/acre)
  6. Can spray with broadleaf herbicides if necessary to control weeds (This article is for seed production in the northwestern part of the USA)

Disadvantages

  1. More costly than straight oats
  2. Slower to establish than straight oats
  3. Seed MUST be inoculated (it may be purchased pre-inoculated)

 

Cowpea

Advantages

  1. Can produce 60-150# nitrogen/acre
  2. Can be broadcast and lightly tilled in (1″ or deeper)
  3. Can be added to other cover crops to add additional value (add to oats)
  4. Can spray with broadleaf herbicides if necessary to control weeds

Disadvantages

  1. Cost and availability of seed
  2. Slower to establish than oats
  3. Seed MUST be inoculated

Other crops to consider: Berseem Clover, Fava Beans, and others.

For further information, please read this excellent article by Barry Fisher, NRCS Agronomist from Indiana, who wrote on this very topic in 2009.

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 Cropping North of I-80 After Corn & Soybeans – A Whole New World?

There is a lot of Iowa and Minnesota and Wisconsin above I-80. Is this all part of the “no cover crops works here after corn and soybeans” zone? Maybe not!

Sarah Carlson from Practical Farmers of Iowa reminded me that cover cropping north of I-80 is different than cover cropping in northern Indiana.  She’s right.  But how different is it, and why is it different?

Sarah is quoted in a very good article in Corn and Soybean Digest that helps explain the differences.

Several farmers in Wisconsin and northern Illinois are having cover crops aerial applied with good success. But I agree with Sarah; there are still challenges.

Cover Crop Challenges in the North

This field of Annual Ryegrass is in SE Wisconsin and was aerial applied into standing corn in the fall of 2011 with great success.

I see the following challenges to using cover crops North of I-80 after corn and soybeans:

  • Shorter growing season after corn and soybean harvest
  • The use of “full season” (for the region) soybean varieties and corn hybrids to maximize yield potential
  • Fear using winter cereal rye (their best option after corn and beans) because of potential risks
  • Fewer choices for cover crop species to use
  • Harsh winters and less snowfall to protect smaller cover crop plants

Cover Crop Opportunities in the North

  • More aerial applicators successfully flying on cover crops into standing corn and soybeans
  • Improved yields following winter cereal rye, a crop that can be planted late
  • High yields and profit with shorter season corn allowing timely application of cover crops
  • Annual Ryegrass is working well in southern Wisconsin and southern Michigan and there are many positive results from using it.
  • Dixie Crimson Clover has a good history of surviving the winter even in mid-Michigan and southern Wisconsin.
  • Late planted Austrian Winter Peas are overwintering as far north as the top of the Thumb of Michigan.
  • Winter Barley (winter hardy varieties) is surviving well in southern to mid-Wisconsin and in southern Minnesota and used for a cover crop or haylage before planting corn silage.

While not every producer North of I-80 will have success with cover crops after corn and soybeans, there are a number now that are happy with their results.

My message is to use wisdom and best management practices.

IF you want to try cover crops after corn and soybeans and you are north of I-80, realize that you are not the first person to try it.  Many have gone before you with good results.

Don’t give up before you investigate the possibilities.

Now, if you are north of I-90…

Cover Crops Provide Improved Corn Yields in On-Farm Trial

All of what is reported below was accomplished after only one year of cover crops.  This work was inspired by a conversation Don and I had last winter with Dr. Eileen Kladivko from Purdue University.  As I say in cover crop meetings,

Don’t expect a miracle the first year – but look for one.

Over the exceptionally dry and super hot late-spring/summer months of 2012 my brother Don Robison collected “plant-health” related data on our corn field at Robison Farms near Greenwood, IN.  Don took data on the corn  from each area of the cover crop plot we planted last fall over the top of a soybean field as well in the “check area” (no cover crop area).

The data he took throughout the summer included plant chlorophyll readings, plant height, and compaction readings.  I presented some of the chlorophyll data on the CropLife Webinar and at several cover crop meetings this summer (and more is posted below).

On August 15th Don and I took hand harvested yield checks from each area and from the check area.   The data on the corn yield was almost identical to what we found with the chlorophyll data and compaction data. Where we had the healthier plants all season long (more “green-ness” and deeper roots) we had higher yields.

To figure yield we utilized this formula we found at a Purdue University agronomy website.

Each cover crop treatment out yielded the “no cover crop check”. The top three yielding plots also had the least compaction and highest chlorophyll readings through out the drought stricken summer.  The check plot yield was 105.24 bushels per acre.  The top yield estimate was 164.82 bushels per acre.

 

The area where the plot was had a 24″ water line was installed by the county in 2009; so it was intended to be a “rescue disturbed soil trial”.  The corn was not harvested directly over the water line but it was where the soil from the water line was mixed in with the top soil.  In 2011 the field was in Soybeans and yielded 48 bushels/acre.  In 2010 the field was corn and yielded 198 bushels/acre.  The whole field has been no-tilled for most of the past 20 years (there were some years with conventional tillage done – mainly in the early 90’s).  175 Units of N were applied (100 units (28%) with the chemical burn down application early season and 75 units side dressed (28%) in early May).

Rainfall from May 1 to July 31 was 2.24″ (with only 0.75 from May 1 to July 19).  There were 42 days over 90 degrees and 8 days over 100 degrees during that time.  All time record dry and heat was recorded in July, 2012 in the area.

Don took chlorophyll readings weekly (one week missed in July due to a family vacation).  He took 30 chlorophyll readings per plot per sampling date.  He also took multiple plant height readings each time as well.  He followed the manufacturers instructions on the chlorophyll readings and penetrometer tests.  Don spent a lot of time in this field so we could all have this data!  Thanks to The CISCO Companies for providing the seed, equipment, and Don’s labor to collect this data.

 

This chart shows the percentage above the no cover crop area (the “check”) compared to the different cover crop mixes. The two comparisons on the far right are from a soybean study we ran where we had cover crops two consecutive years compared to one year (more data and a post coming soon on this study).

Observations:

  • The plot areas that rated healthier (more green-ness and taller) yielded the best.
  • The plots areas where there was less compaction yielded the best
  • The plots with annual ryegrass did not fare as well as some others in this drought year – yet was still considerably above the check.
  • Not all plots with radish were “top” yielding – however two of the top three yielding plots had legumes plus radish.
  • Plots with legumes were generally healthier all season long and their yield reflected that.
  • I doubt that the whole field will average over 100 bushels/acre.  As with all hand yield tests they are estimates but I believe that the comparison is very accurate.
  • The Austrian Winter Peas, Crimson Clover, and Appin Turnips overwintered “beautifully” and were growing aggressively when sprayed at burndown.
  • There was a considerable amount of earthworm activity in the cover crop area but only a few earthworms were found in the “check” area. That is unfortunate because 2 acres were covered and 48 acres were not!
  • There were more corn roots in the plot areas we dug vs. the check area (watch for a new post coming on this soon).
  • There was more moisture in the soil where the cover crop plots were compared to the check area.
  • The soil structure was considerably better in each cover crop plot vs. the check area.
Don recorded over 180 chlorophyll readings in each cover crop plot and check plot over the summer.

 

The check plot had 175 units of nitrogen plus the whole field had been soybeans the previous year. While the annual ryegrass blend plot was above the check all season long it was not up to the desired level until after the July 19 rain event.

 

The plot with the Oats and Rye and Appin Turnips was impressive most of the spring and summer. It was at or above the desired rating until August. It was very impressive right after the July rain event and that is possibly why it had the second highest estimated yield. By the way, the turnips did live through the winter.
All season long I was convinced that the plot where the Austrian Winter Peas and Radish were was going to have the highest yield based on the data shown above (and plant height readings). It beat the second place entry by less than 1/2 bushel in the yield estimate.

Inoculating Cover Crop Legumes Pays Off

Several farmers have asked me why they need to spend an “extra” 4-6 cents per pound to inoculate the legume seed they are planting for producing nitrogen with their cover crops.  I get asked this especially about Austrian Winter Peas and Cowpea.

However, if you are planting Crimson Clover, Berseem Clover, Kura Clover, Alsike, Hairy Vetch, Sunn Hemp, or Medium Red Clover it’s just as important inoculate!  Why?  I’ll list a few reasons below:Inoculated peas are significantly better at producing nitrogen

  • Legumes are planted as cover crops most specifically to produce nitrogen.
  • Legume seed is relatively expensive; if it does NOT produce nitrogen, then it is exceptionally expensive.
  • The inoculant is a species specific bacteria that allows that plant to fix nitrogen.  If there are not enough bacteria there is limited nitrogen production from the legume plants.
  • A healthy legume cover crop can produce nearly 200 units of nitrogen
  • Even if you have produced a similar crop in your field within a two year time period, it still pays to inoculate each year since many of the bacteria prove to be “weak” and unable to perform like a healthy and vigorous bacteria.
  • If inoculating Peas or Cowpea you will need to do a “seedbox” treatment.  There are not yet inoculants that can be pre-applied that will allow you to have healthy bacteria. Therefore, most inoculant companies suggest putting the inoculant on within hours of putting the seed in the ground.

Be sure to get very good coverage on all of the seeds.

Do not hurry. Each seed needs coverage to actually be inoculated. I know that sounds silly, but I have seen many fields and plots where only some of the pea or vetch  plants were performing well.  The ones that looked poor had no nodules.

Many companies sell pre-inoculated clover seed.  If yours does not, then either find another supplier or purchase the correct inoculant from your current seed supplier.  Do not waste a great opportunity to produce as much nitrogen as possible. It is  less expensive to produce nitrogen than it is to purchase it.

A well inoculate Austrian Winter Pea nodule will be pink inside like the one above.
This photo shows a mixture of well inoculated and poorly inoculated Austrian Winter Pea plants. It is important to inoculate each seed with the nitrogen fixing bacteria.

 

 

Planting into “Out of Control” Peas – The Rest of the Story

In September 2011 I posted about an Ohio farmer that planted into “out of control” peas and shared about his story of how the field was looking pre-harvest.  I have recently visited with Dave (the producer) and he shared the information that a number of you asked for…and also surprising yield data. Dave farms with his father-in-law Ron in Mercer County, Ohio near Rockford (NW Ohio).

Sometimes it takes courage to farm with cover crops! Dave and his father-in-law Ron planted with confidence as the ground was "very mellow" compared to other ground without a cover crop.

Here are Dave’s observations and the 2010-2011 field history:

  • Hog Manure applied late summer of 2010 – 5000 gal/ac
  • No other fall fertilizer
  • N-Vest Groundbreaker Mix (Austrian Winter Peas and GroundHog Radish) planted Labor Day weekend 2010

Peas that survived – and other weeds, wheat, clover, etc. – were sprayed (after a wet, wet spring) on June 2, 2011.

________________________________________________

Herbicide/Insecticide Mix: (rates per acre)
20 gal Water
Alliance – .2 gal   (1 gal/100 gal water)
Roundup WeatherMax – 44oz
Weedone 650 – 1pt
PowerLock Surfactant – 6oz
Baythroid (insecticide) – 2oz

Corn was planted on June 3, 2011.

Additional Fertilizer applied (in addition to nutrients from manure and N from peas)

20 gal/ac 10-34-0 starter fertilizer with 1qt/ac zinc

40 gal/ac 28-0-0 side dress with Agrotain N stabilizer

Results

Even though several acres in the area were too wet to plant this field of peas was in great shape as you can see the row closed "perfectly" behind the planter.

Weigh wagon test showed 215 bu dry yield.  Dave guesses the whole field average was between 200-215 dry (he has no scales at home to check weight of entire crop).
Dave also thinks that the yield was 10-15 bu better that most of their other corn (w/o manure and w/o cover crops).

The seed placement of this no-till planting into the peas was "near-perfect".

All things considered…the wettest spring in Eastern Corn Belt History, late planting date, planting into 3+ foot tall peas, < 1″ of rain in the month of July (with 22 days 90 degrees or more), a wet fall that delayed harvest..and the result was over  200 bushels/acre.  I’d take that everyday for that part of Ohio, and so will Dave and his father-in-law Ron.

The roots on the peas were massive by early June. Don't expect this in most years but this certainly did not hinder planting, getting a good stand, or attaining a very high yield!

Other observations from Dave:

Positives:

Better soil structure

Deeper root penetration by corn roots

Great seedbed to plant into

Great soil cover after cover crop was killed

Better water retention thru the dry months

Nutrients saved from hog manure

Negatives:

Too much growth in wet spring

Took a lot of time to plant due to pea growth

 

Thanks Dave for sharing your story!

Cover Crops in the Great Plains – a view from a long time cover crop user- Part 2

In this cover crop post I again quote Paul Conway from Kansas, who is giving his input on cover crops in the Great Plains. In this article, Paul shares his experience with Austrian winter peas, field peas, chickling vetch, and hairy vetch.

Dave,

Austrian Winter Peas: I have limited and disappointing experience with Austrian Winter Peas.  They always winter kill and they must be planted at an inconvenient time.  It seems that the areas where they do well do not follow a simple geographical line.  Austrian Winter Peas do very well about 60 miles south of me in central and southern Kansas.  Ironically, they seem to do fine in the Nebraska panhandle, which is much colder than we are. I think consistent snow cover makes the difference.

Field Peas: also know as Canadian field peas or forage peas. I’ve grown these in early fall with oats and forage radish. I don’t know how much nitrogen they fix but they do winterkill by early winter –  mine haven’t died yet – probably consistent lows in the middle teens will do it.

I also plant them in early spring the same time as oats, killing them for June planted cash crops.  Mowing after flowering will effectively kill peas.  Where peas shine is in mixes and in cool climates.

The pea/oat or pea/triticale is excellent for haylage or silage. These mixes have the same benefits for livestock farmers as the soybean/summer grass mixes.

In much of the Midwest and east, double cropping is possible, oat/peas followed by soybean/milo or sorghum-sudan.  Further north, the oat/pea mixes would mature too late.  In that regard, I think that field peas could be managed as a summer annual (like soybeans) in the Great Lakes states, upstate New York, Pennsylvania, and New England.

Peas can handle routine summer temperatures in the low-mid 80s. Peas can be grazed. Peas aren’t shade tolerant so they don’t do well when sown into row crops.  Frankly outside the mixes I think the clovers may be more versatile.

Chickling Vetch: Also known as “AC Greenfix.” It will fix nitrogen faster both in the fall (it winterkills about the same time as the peas) and in the spring.  AC Greenfix seed is more expensive and harder to plant due to it’s shape.

Hairy Vetch: As you know, hairy vetch is the strongest nitrogen fixer among the annuals.  Hairy vetch easily fits into vegetable rotations. I have seen two foot vine growth and numerous fat nodules on vetch in early-mid April after a mildly wet fall and an early spring.  It will be harder to fit into field crop rotations, especially corn-soybeans.

Here the optimum time to plant hairy vetch is September, but it can be planted as late as mid October.  It needs minimal soil contact which isn’t a problem in a normal fall. A dry September/October, like I had this year, is a problem.

I know that you have some experience with flying in hairy vetch into maturing corn or soybeans.  Another option is to plant it very late (mid-late November) and hope it doesn’t germinate until the soil warms up in late winter-early spring.   I don’t think people realize how versatile hairy vetch can be.  In the northern areas suited for field peas (see above) hairy vetch could be managed as a summer annual. [I have seen hairy vetch flower, drop seed which stays dormant during a hot dry summer – Dave’s EMPHASIS HERE – this is why I caution growers about Hairy Vetch.]  When the weather cools down in late August the vetch seed sprouts.  It is still warm then through September and early October with temperatures similiar to the Great Lakes states and New England in the summer.  So why couldn’t vetch be planted in early summer in these areas?

Years ago I planted hairy vetch in April between wide rows of vegetables just to see what would happen.  I remember lots of growth by July, despite a hot dry summer. The soil under the vetch was cool and moist.  The vetch did not grow enough to fix much nitrogen by May but it may have fixed enough nitrogen for mid-summer planted crops.

In 2012 I will plant hairy vetch and other vetches (purple) in the spring and record how they do.

Finally, new cultivars of hairy vetch come out which may have promise.  I will try a new variety called Purple Bounty, which is supposed to mature two weeks earlier but with less winter hardiness.

 

Nutrient Scavenging Cover Crops – How much good are they doing? It depends.

Meet the Cover Crop Scavengers

Over the years I have worked with cover crops I have recommended that producers use “scavengers” like Annual Ryegrass, turnips, cereal rye,  winter barley, oats,  and cover crop radishes.  These cover crops do a very good job of capturing excess nitrogen and other nutrients and keeping them from reaching the ground water or running off with surface water.  When the nutrients are scavenged they are available for the subsequent crop.

Most of these scavengers are “luxury consumers” of nitrogen and a few of them are also “luxury consumers” of phosphorous.  These are ideal to use on land where manure is applied.  They also work very well when grown with a legume like crimson clover, hairy vetch, chickling vetch, and Austrian winter peas.

However, if  limited amounts of nitrogen are available how will these scavengers perform?

The answer: not as well.

My answer is subjective but based on observations that I will show you via some photos.

 

Observation 1

It is easy to see where the manure was knifed in in this field. But how much more N is being taken up where it is darker green? We'll be doing tissue tests soon to determine that.

The first observation is where hog manure was knifed in after wheat had been harvested. The photo shows that the cover crop (Annual ryegrass and Appin turnips) looks considerably darker where the manure had been applied.  We will soon be taking tissue samples to see what difference there is in the amount of N, P, and K are in the plants.  We also anticipate a future post showing a root pit view of the root growth difference (if any).
 
 
 
 

Observation 2

The "yellow" strips are pretty obvious in the cover crops in this seed corn field. It is not obvious where the corn rows were but I expect the lighter strips are above where the corn row had been.

The next observation comes from a seed corn field in north western Indiana near Demotte in Jasper county.  The main area of difference in N uptake is found where the male corn rows had been cut out this summer after the female rows had pollinated.  The difference is color was not as dramatic as it was in the previous situation but there was a clear difference in color and the amount of growth (considerably more developed) of the cover crop.
 
 
 
 

Observation 3

The left half of this photo had 35#/acre of N but had no legume to feed the radish. The right half of the photo shows the significant color and growth difference when radishes are grown with crimson clover (and the 35# N/acre).

The next field is near Edgerton in NW Ohio.  This field had three different applications being trialed.  One area had a crimson clover and GroundHog radish mixture, another area had an Austrian Winter Pea and GroundHog Radish mixture.  In between these mixtures was a strip of Tillage cover crop radishes with no legume but with around 35 units of nitrogen applied (the ~35 # of N was applied across the whole field).  If you attend many cover crop meetings you will hear speakers tell you to apply 35-50 units of N on radishes if they are sown without a legume or without manure applied.  After seeing this field I believe we are underestimating what kind of N we need to apply for “best” results as the radish only strip had considerably smaller radishes with much less tuber growth and more “yellow leaf”.    The area with the crimson clover/GroundHog Radish Mix was by far the darkest green and had the largest radish growth.  However, even though the peas did not look as impressive as the crimson clover, the radish growth was significant and much darker green than the radish area grown without any legume.

Observation 4

Not only does the crimson clover add nitrogen to the soil it also greatly enhances the soil structure. The soil on the left came from where there was only radishes planted. The soil on the right had crimson clover and radishes mixed together.

Another observation from this field was that where the radishes were grown with the crimson clover the soil had a much improved structure over the soil where only radishes were grown.  The massive amounts of crimson clover roots (with an exceptional amount of nodules on them by the way) gave the soil a much better texture.  See a very descriptive video here.  These soils are “Williams County Clays” or “NW Ohio clays” and are well known for their tightness and poor drainage.  As the farmer Ryan Sanders said after seeing the results of this experiment… “I will never plant radishes alone again.”

 

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.

Farmer Report from Ohio – Planting into “Out of Control” Peas

The cover crop radishes varied in size with the amount of moisture in the field in the fall of 2010.

My good friend David from Mercer County, Ohio is a great cover crop advocate.  Over the past few years he and his father-in-law have begun planting cover crops after their wheat crop is harvested.  The first year he planted oats and cover crop radish and this past year they planted a mixture called N-Vest® Groundbreaker Mix (a mixture of Austrian winter peas and cover crop radishes).  The summer of 2010 set some records for being exceptionally dry.  Neither the peas nor radish grew the way anyone hoped for, but David did find radish roots around 20 inches deep.  The peas were less than spectacular but still acceptable for as dry as it was.

No-tilling corn into this mix of peas and wheat looked like an easy task in early May when this photograph was taken...but the rains kept coming!
This is not what was expected! Early June 2011 was wet and the peas were tall.

As I have reported in several previous posts, the weather in NW Ohio and the Eastern Corn Belt was the wettest in 120 plus years of keeping records.  The Austrian winter peas and volunteer wheat over-wintered.  In early May David was convinced that they would no-till directly into that “mix.”  But the rain came and came often! By early June the peas had grown quite a bit, like up to four feet tall…and that is what they no-tilled into.  Actually, David said it was the “most mellow soil” he planted into all spring.

Just a few days after planting David sent me the photos of a beautiful stand of corn where the peas had been over 4 feet tall.
Three weeks after planting the corn looked great and the cover crop was dead. This photo was taken June 21, 2011.

I joke that David was nearly written out of the family will when he started no-till planting his corn!  The neighbors were all watching but David persevered and kept planting…even though it was not as easy or as early as he hoped it would be.  A few days later David e-mailed me more photos…and then a week later more photos…

Exactly four weeks after planting and the corn looks remarkable.

So now the neighbors are wondering about this David “kid” that married into this operation.  Maybe he is not as foolish as they thought earlier in the spring!  Exactly four weeks after planting the corn was over “knee high by the 4th of July” and now the neighbors are asking what that cover crop was!

In mid-July, six weeks after planting and the weather has been HOT and dry...but according to David, the field "shows less stress" than conventionally tilled field that had no cover crops.

But the dry summer of 2010 was now being duplicated by another dry summer and the summer of 2011 has been much hotter than 2010.  So how has the no-till corn fared during these challenging conditions? Very well, actually.

There was less than 2" of rain in a very hot July and yet the field looks quite good considering the heat and dryness that it has experienced.

So will David plant cover crops again?  Yes!  In fact they are already in the ground and waiting for rain to emerge.  David has been very excited all the way through this process as he has been confident he is doing the right thing for his soil and the future of his farming operation.  Thanks to David for providing the photos and information to encourage all of us that cover crops are an exciting option that we should all consider.