The photos here arrived today from a central Iowa grower who sprayed cornstalks Oct. 17 with a pint per acre of Environoc 501 plus some microbial “starter fluid:” two gallons per acre of calcium chloride. Softer pith in the stalk has already gone dark after slightly more than a week of mild temperatures. By spring, these stalks should be crumbly and enhancing the no-till seedbed.
October 26, 2017 — The photos were taken in central Iowa Oct. 26, just nine days after spraying the stalk field with the combination of beneficial bacteria and fungi designed to digest tough lignin, cellulose and other high-carbon crop residue. Those days had mild temperatures, and the bugs-in-the-jug immediately multiplied. Some species reproduce about every 20 minutes.
Softer pith in the center of stalks is already so heavily colonized that it has turned black. Untreated stalks (the four on top) look almost unchanged from when they were harvested.
It’s important to build a microbe mix that has a variety of both fungal and bacterial organisms. The bacteria munch quickly. The fungal species work more slowly, but these are the creatures which build glomalin, the sticky mucilage of polysaccharides and carbons which help build soil granules into the well-aerated “coffee grounds” structure.
Cracking open cornstalks helps moisture and microbes penetrate into their soft underbellies, so they decompose from the inside out. Today’s new traited stalks have a tough lignin rind and waxy surface that’s slow to break down. The 501 has a specialized organism which attacks lignin. Others favor cellulose.
In a second photo from the treated area of this field, husks and shattered stalks on the ground are gray with fungal and bacterial colonies. The objective: By spring, stalks are fragile and shatter easily when hit with a planter’s disk openers. No-till farmers are finding that with excellent and early stalk digestion, trash whippers are not crucial because the trash is like ashes — crumbles with slicing steel, rather than hairpinning in the furrow. Result: Much more uniform emergence, which is critical for yields. A seed which emerges four days later than its neighbors suffers a loss of about 40 bushels of yield potential. It’s a runt, battling allopathic pressures from faster-emerging nearby roots.
We’ve heard farmers say they don’t need accelerated cornstalk breakdown because with cover crops and a good microbial balance in the soil, their stalks have mostly degraded by late June or early July. But both of those months are times of surging nitrogen demand by corn’s vegetative growth. And the microbes eat nitrogen first. Ideally, visible residue would be crumbly within a few weeks after planting.
This farmer used calcium chloride as an “accelerant” for early microbe fuel. Other growers may elect to use liquid 28% nitrogen; The parent company, Redox, is offering a formulation designed to apply broadcast with 28% or 32% nitrogen.
One astute grower questioned the use of two gallons per acre of calcium chloride as a microbe booster. Our source book on “Mineral Nutrition and Plant Disease” observes that “In nature, the chloride ion (Cl-) is widely distributed and subject to rapid recycling.” It adds that “The beneficial effects of Cl- fertilization are not fully understood, but improved plant-water relationships and inhibition of diseases are two important factors.”