Renewable Farming

How corn growers gain 40 bu. or more with full-season crop health and nutrition

This winter offers your opportunity to create a strategy for full-season corn crop health in 2017. That calls for countering the trend we’ve seen the past several years: Corn dying a few days earlier each season.

Dec.26, 2016 — Keeping corn leaves green until frost, especially the leaves above the ear, is a major source of kernel depth and test weight. Corn contest winners achieve this by foliar-feeding what the crop is calling for — through the full season. 

That can generate deeper kernels, which show up as “fat” ears filled completely to the tip. Test weights are typically well over 56 pounds per bushel, amplifying yield. 

These photos from Iowa corn grower Dave Schwartz reveal the results of an aggressive nutritional approach through the growing season. The first photo is an example of long, dense kernels. 

Long, full kernels on Dave Schwartz’ corn

Depending on the genetics and complete nutrition, some “dent” hybrids have a very shallow kernel dent extending from the base of the ear almost the full length of the ear. That’s a signal of complete kernel fill.

This ear comes from a field that yielded well over 300 bu. per acre. Dave’s own combine had a yield monitor programmed with a 300-bu. top limit, so he used a neighbor’s combine and monitor to verify that corn was coming out at 300 to 340 bu. on his better soils.  We published a more detailed account of his report in late November; it’s at this link. The linked story offers a summary of the full-season nutrition program which Dave applied.

When leaves die back starting in early September or even late August, there’s no way to fully capture the final 60 days of sunshine the season offers you. Yet, we see only a few crop consultant and farmers alarmed about early die-down. It has tiptoed up on us a little each year; now it’s shrugged off as “normal.” Seasoned crop consultants such as Dr. Michael McNeill raise the issue:  “What has changed? Why is this happening?”

Several of our neighbors here in northeast Iowa tell us they’ve gained 15 bu. or so by flying on fungicide after corn’s brown silk stage. Sometimes they apply two treatments. That offers a clue that fungal disease is at least part of the reason for premature die-down. 

However, we hear few farmers — other than corn contest winners — talking about how they use nutrition as a way to build crop immune systems against pathogens. Usually the farmer’s reaction is: Kill the bacteria, kill the fungus.  With that approach, the applied toxins can impact beneficial organisms, too — organisms essential for nutrient conversion and crop self-defense against disease.  

Dr. Don Huber and other researchers have documented how nutrition can help crops defend against disease. One of the best assemblies of that research is packaged in this book, Mineral Nutrition and Plant Disease. 

It’s available at; visit this link to find it.  It’s the kind of resource that takes “thinking time,” so your January escape to Florida or southern Texas can become very profitable in the long run — if you take this volume along and study it. 

Fortunately, newly emerging agronomic supply firms are doing their homework and offering the techniques and nutrients which appear economically effective. Even with cash corn struggling at $3.20 or so.

One immune-building product, which we field-test tested in 2014 and 2015, was used by Dave Schwartz in 2016, in addition to foliar-applied nutrition through the season. It’s “Bio Empruv,” created by a biological expert working with Ken Hamilton and his company, Bio Minerals Technologies. Unless that website has been updated after December 2016, you won’t find much about the Bio Empruv. It was essentially rolled out in “beta” field research in 2016. Plans are underway this winter to offer it to a larger audience. Dave Schwartz will be instrumental in this, via his marketing connections. 

We want to point out that in our field trials, tank-mixing WakeUP Summer with foliar-applied Bio Empruv enhanced yield performance of the Bio Empruv.  That’s consistent with the response, in our tests, of other biostimulants and immune builders such as Vitazyme and Lignition when we’ve used WakeUP Summer to improve coverage, absorption and nutrient transfer.

Another learning curve to climb is testing the tissue or sap of your growing crop to detect hidden nutritional needs before the limitations constrain yield potential. We’ve been encouraging sap testing, and hoping that the “home office” of sap testing expertise in the Netherlands would establish a laboratory in the United States. Currently, samples of growing crops must be flown to the main laboratory of Nova Crop Control in the Netherlands. Even with the flight time, sap testing still gives you a two week or more advantage over tissue testing to detect and correct nutrient shortfalls in the growing crop.

We suggest that you visit the Nova Crop Control website and read up on the advantage which sap testing offers for season-long nutritional guidance.  

The U.S. connecting point to channel samples to Nova Crop Control is Crop Health Labs of Belleville, Ohio. We’ve used their services, and have been pleased with the turnaround time. However, you need to set up an account, obtain the standardized sample bags and learn the sampling technique.  For example, with sap testing you pull two samples from the same area for each crop analysis: lower leaves and newly emerged leaves. The differences help reveal if the crop is cannibalizing nutrients from older leaves to maintain growth. 

You’ll also benefit by looking into a new concept: Using phosphite minerals as a means of building crop immunity against pathogens. Phosphite, applied in a foliar along with trace elements such as manganese and zinc, has shown crop health benefits. This is an emerging technology which wasn’t covered in the book, Mineral Nutrition and Plant Desease, published in 2007. We’re in touch with two Brazilian firms with several years’ expertise in foliar-applying various phosphite materials. We had to keep in mind that phosphite should not be compared with the major nutrient, phosphate. 

The most active marketer of foliars containing the phosphite technology is Spraytec of Brazil. This firm hosted a well-attended seminar in Des Moines for farmers Dec. 13, which we attended and reported on.

The profit rationale we are searching for in these newer technologies: Spend less on toxins to fight disease, spend less on bulk NPK, and invest the savings in more precisely applied nutrition that maintains season-long crop health. In effect, use your management skills more; your checkbook less. 

Years ago, Dr. Dan Skow and his partner Wendell Owens of International Ag Labs taught us: “Winter is when the best farmers make most of their money.”  They were of course referring to cultivating your knowledge, not your soil. 

Here are further photos sent to us by Dave Schwartz, who’s just one example of full-season corn nutrition:

A field of Dave Schwartz corn as of Aug. 22, 2016. Many of the surrounding cornfields were dying down by then.
Corn at harvest time: Maturing ears, but mostly green above the ear
A “fat” ear… showing the result of extra kernel depth added late in the season