A synergistic way to accelerate recapture of your valuable cornstalk carbon

First, crunch those tough, tire-jabbing cornstalks. Second, spray on a residue-digesting blend of lignin-loving microbes that will chew through cellulose and lignin. This one-two punch converts more raw carbon from stalks to humus. Then over the following weeks, the active humus meters out stored nutrients to your crop. 

Sept. 11, 2018 — On this date, Sept. 11,  it's appropriate to present an idea that's positive and shows America's resilience and determination to build the intrinsic strength and health of America. In a small way, that's what this report is about: Rebuilding our soil, the foundation of America's health. 

One small step into this venture is a field study sponsored by two American firms, Yetter Manufacturing and Biodyne USA. The idea: First, shatter cornstalks — with a combine header attachment — to make it easier for beneficial bacteria and fungi to reach and devour the soft inner juices. Then, quickly as possible, inoculate the corn residue with a fast-reproducing array of organisms selected for their ability to digest high-carbon crop residue. The mechanical crushing enhances the biological breakdown.

Ordinarily, field research attempts to objectively quantify results. In a project like this, numbers are hard to obtain. However, a corn grower can visually see differences in stalk breakdown, and feel differences in stalk toughness. The photos here, taken Sept. 8, 2018, attempt to see those changes after nearly a full season of residue breakdown. The soybeans were planted into 2017-crop corn ground. Some strips were not treated with either the residue digestion product (Environoc 501 in our experiment) or the Yetter Devastator, which is a roller edged with crimping blades and mounted beneath the combine header. We described this unit last fall at Steve Schmidt's farm

Fall 2017: Yetter Devastator on Steve Schmidt's combine

One obvious advantage of the Devastator is that when you're done combining, you're also done cracking and crushing the stalks. Other farmers prefer to run a flail shredder over the field to shatter stalks into smaller fragments. The Devastator also flattens and crimps stalks just ahead of combine drive wheels, so the tough stubs aren't relentlessly chewing up your expensive tires. After we looked at Steve's field last fall, we invited Yetter marketing manager Andy Thompson to participate in this further study, and he agreed.

Steve will be making soybean yield checks in each of four treatments:

1. Fall Devastator but no Environoc 501

2. No Devastator, no Environoc 501

3. No Devastator, but fall application of Environoc 501 on untouched stalks

4. Fall Devastator plus fall application of Environoc 501 on Devastated stalks.

Meanwhile, we'll show you an update of stalk conditions in the two plots with the clearest visual differences: No 2 with no treatments and No. 4 with both treatments.

The first residue photo is looking north in strip 2 — no-tilled directly into untreated stalks. This photo was taken Sept. 7, 2018 so the stalks have had the full growing season to break down. The only field traffic over them was the combine last fall, then the planter and sprayer this spring. No cultivation. Many of the stalks are still intact — not even cracked open. Many of the smaller pieces haven't disintegrated yet.

Biodyne USA's advice is that its biological products are long-term soil builders, rather than providing immediate yield response. We'll soon get some clues on yields from these strips. Other field experience with fall-applied Environoc 501 followed by in-furrow Environoc 401 has shown clear-cut yield gains.

The second residue photo comes from a strip about 60 feet from the first which was crimped with the Devastator, then sprayed last fall with Environoc 501. This 501 application wasn't made right after harvest, but the field did have a couple of weeks of 50-degree temperatures after spraying and before freeze-up. We encourage spraying as quickly as possible behind the combine. Some corn growers hire temporary help to chase the combine with a residue spray solution. 

In the 501-treated strips, only a few chunks of cracked stalks remain. Very few crumbs of the smaller stalk pieces are visible, and those crumble at a touch. The coverage looks consistent all up and down the strip. 

We've heard about other growers who do extensive cover crops, plus running a Devastator, and say that their soil biological life is so active they don't need an inoculant to jump-start stalk breakdown.

With all the newly introduced residue digestion products hitting the market, we've found no simple way to say, "This one is better." It would be worth some side-by-side experiments to check out which ones appear most aggressive in doing the job for you.

The Old Faithful we've known for years is Residuce, from AgriEnergy Resources. 

Environoc 501 was formulated by a long-experienced microbiologist who put together microbe blends for many purposes, including remediation of petroleum spills. One or two of the organisms in 501 is designed to devour lignin, which is the outer shell of cornstalks. The traited hybrids have especially tough stalks.

We welcome comments and reports on other residue-breakdown ideas.  Just e-mail us.