Veteran plant pathologist Dr. Don Huber often comments in his seminars on crop health that “Corn used to be one of the healthiest crops on American farms.”
But now that much of the Midwest sees early corn die-down, is there a way to recapture the 40 to 60 “home stretch” days of corn maturity, when corn kernels are adding depth and weight by about a bushel a day?
Oct. 30, 2017 — A few corn growers are trying hard to achieve full-season crop health by restoring healthy soil and crop biology. The photo here, taken by agronomist Mike Williams of Gold Eagle co-op in central Iowa, offers some encouragement. It was shot the day before the first hard overnight freeze in this region — in the mid-20s. The stalk has matured normally, and most of the leaves still have some functional green areas. The corn’s phloem and xylem circulation system is still open and flowing. Before kernels black-layered, nutrients were still flowing into kernels and adding to yield. And even after physiological maturity, an open circulation system allows moisture in the matured kernels to flow back out, reducing kernel moisture more rapidly than air-drying alone. That’s the way it used to be, as veteran crop consultant, Dr. Michael O’Neill often tells farmers.
While most mid-Iowa cornfields went uniformly brown more than a month ago, a few remained alive and healthy. Like this one, which was defended from pathogens by beneficial bacteria and fungi in the root zone. This field had a Biodyne Midwest in-furrow infusion of “Environoc 410” with the planter. A few other fields in the region had a residue digester, Environoc 501, sprayed on stalks in fall 2016, which added biological benefits to this year’s corn crop.
How late can you apply a fall residue digester on stalks and still gain worthwhile acceleration in stalk decomposition? Mike Williams says it’s effective whenever daytime temps are above freezing. “A week of freezing temperatures, and you’re done,” he adds. After that, early spring becomes the next opportunity for broadcast residue digester products. We got off to a late start in discovering the Biodyne Midwest residue digesters, and shipped out our first Environoc 501 to clients last week. Call us if we can help you with any residue digestion questions.
The pith in those mostly green stalks is still flowing with plant sap. Mike’s fingers were wet with juicy sap after breaking a stalk and squeezing the soft inner pulp. This sugary juice is ideal energy for beneficial fungi and microbes. See our earlier articles on how to accelerate residue breakdown.
Several agronomic providers offer residue digesting blends of mycorrhizal fungi and bacteria. Probably the “veteran” in this field is Residuce, which we’ve used for years on our research farm. Now, with more intense interest in biological agriculture, your choices are widening. AgriEnergy’s recent “Ground Work” column acknowledges that these choices raise the question of what’s most effective for your soils. Certainly there’s a spectrum of biological life which differs between regions and farms, just as soil types and cropping patterns do. So we suggest “test and observe.”
The following summary on fall residue treatments was written by an AgriEnergy agronomist and published earlier on the AgriEnergy Resources website. An important note — AgriEnergy’s Residuce products come as dry powdered organisms in their dormant state. This is what gives them long shelf life. most other crop-digesting biologicals are “bugs in a jug” which arrive as liquids and are subject to freezing and aging. Suggested life of Environoc 501, for example, is that you can keep it over winter for spring application, but after six months, the liquid blend can benefit from an infusion of fresh microbial concentrate from the company. Here’s AgriEnergy’s description of their approach:
We often refer to a complete residue management program that includes our Residuce® line. While we’ve seen how beneficial proper residue management can be, it is confusing deciding which combination is right for you. One great thing about this line is that these products have a long shelf life, so if harvest gets late, it will keep for an early spring application. Hopefully, the following key can help make the choices clearer.
First, there are 2 options for the microbial package – Residuce® WS and Residuce® Complete.
- Residuce® WS is a concentrated microbial package. In most field situations, requiring only 1/10 pound of product/acre.
- Residuce® Complete is a complete dry package, containing both the microbes and powdered food sources. This can either be spread dry or solubilize in water. Typical rate is 2 pounds/acre.
If you use Residuce® WS, it is important to include a food package for the organisms. There are several products available for both conventional or organic.
For the conventional grower:
- Residuce® XT is a combination of nitrogen and carbon sources. It’s very clean and compatible with herbicides.
- Residuce® CS is a combination of carbon food sources and humic acids which have the added benefit of loosening compacted soils.
- Practi-Cal is a unique combination of liquid calcium, humic acid, and micronutrients that is particularly effective on tight clay soils.
For the organic grower:
- Residuce® O is a package of organic components that are used as food sources to stimulate the microbes.
- CALiber is the organic version of our PractiCal.
For extra soil conditioning, Bio Humus can be added to either the conventional or organic liquid packages. This is a good option for those fighting compaction.