We’ve always encouraged corn growers to look inside cornstalks in spring, from about the four-leaf stage on, to detect early signals of brown, rotting gunk in the xylem tubes near the root crown. That’s a barometer of season-long root health, thus showing the stalk’s ability to transport water and nutrients to leaves and kernels.
October 18, 2018 — With today’s increased appreciation for fall stalk digestion, splitting stalks after harvest offers insights into how fast you can coax a cornstalk into its conversion from lignin and cellulose into active humus.
Larry Eekhoff, crop consultant and owner of Agronomy Rx of Webster City, IA, today sent us photos (taken yesterday) of stalks treated a month ago with Meltdown, the new blend of residue digester from Biodyne USA.
Larry also sent two brief videos, which we posted below. Here’s the main message: Splitting the stalk helps reveal how quickly your residue digestion bacteria and fungi are chewing the stalk from the inside out.
In this field, stalks weren’t flattened or cracked with a Stalk Stomper or Yetter Devastator. Yet, organisms multiplied their way down the xylem tubes rapidly. It’s another signal that a healthy, juicy stalk is a far better meal for microbes than a dead one defended by disease organisms. Healthy stock digestion is much more favorable for your future than stalk rot by pathogenic molds — which now show symptoms in about 85% of north central Iowa fields.
Larry’s videos just below reveal how crop digestion organisms migrate into roots, softening them to make them easy to pull. The first Meltdown trial shows how tough it was to pull a cornstalk from an untreated part of the field, about a month after harvest.
The second video shows how easy it was to pull a stalk from an area of the field which had been sprayed with Meltdown about a month before these videos were shot.
Another plus for digging and splitting stalks in the fall: You get a postmortem view of how well your management has kept your stalks healthy through the growing season. The nearly pure white pith, and minor browning at the root crown, indicates that Larry’s farmer client has kept this corn healthy all season. That’s a huge contrast with most of the fields in his area this fall. Stalk rot is increasingly invasive in north central Iowa.
Oh yes… full disclosure: Renewable Farming can supply you quickly with the best stalk residue digesters we’ve found available in the market. Cost of the newest, MELTDOWN, is about $10 per acre. Here’s our contact information.
Residue digester organisms remain active in the fall until soil temperatures stay consistently below 45 to 50 degrees. Farmers who’ve seen the benefits of these stalk-reducing microbials typically find ways to get them applied, even in a fall when harvest is hectic or delayed. Some hire a retired farmer to run the sprayer, following the combine. Farmers with expensive high-clearance GPS-controlled sprayers are often hesitant to keep them active in the fall, as night temperatures dip below freezing. In our own experience, we’ve used an older $2,500 pull-type sprayer, towed by a utility tractor with a heated cab for comfort. You don’t need GPS or precision application, and a 60-foot boom is plenty to keep up with the combine.
Other corn growers put a spray boom on their stalk chopper, carrying the spray tank on a towed caddy or saddle tanks (remember saddle tanks?).
Benefits from breaking down the tough stalks left by today’s hybrids include these four:
1. Convert lignin and cellulose to active humus sooner, so the microbes aren’t scavenging nitrogen away from next spring’s growing crops.
2. Smoother, more constant planting depth as your planter coulters slice through crumbled stalks rather than hairpinning tough, undigested stalks in the furrow. Uniform planting depth is crucial for uniform emergence — a key to optimum yield. A stalk emerging two days after its neighbor is typically a runt with a yield penalty.
3. Deprives pathogenic fungus a place to overwinter.
4. Active microbial growth can help neutralize herbicide residues, reducing carryover activity of those weedkillers.