Every bushel you add in the fall leaves more stover behind for spring.
“The challenge behind residue is that every time we create higher yields, we actually create higher residue levels,” says Matt Sowder, director of field solutions at Mosaic Biosciences. “If you grow crops, you don’t get out of it. Everybody gets to deal with it.”
Most growers still handle that residue with steel, diesel and time, not a digester. Sowder estimates fewer than 10% of corn stubble acres get any chemical or biological residue product today.
“The market’s not really congealed around anything,” he says.
Mosaic thinks it can change that. The company launched Renuvis Enzara, an enzyme-based residue digester, in August. Its suggested retail is around $10 an acre, and the product is sold through Mosaic dealers.
Whether $10 pays back depends on which return you’re buying. Sowder describes three: field operations, stand establishment and nutrient release. When you spray it decides which of the three you get.
Why enzymes aren’t just a faster bacteria product
Renuvis Enzara is enzyme-based which makes it distinctly different than most residue products on the market that rely on bacteria. Sowder says bacteria are the bottleneck.
“Bacteria are slow to perform. Typically, bacteria go to sleep below 50 degrees Fahrenheit,” he says. “Enzymes work on a chemical potential gradient. And so, even though they might slow a little bit as the temperature decreases, they’re still active all the way down to freezing, and yes, they do survive the freeze-thaw cycle.”
Renuvis Enzara uses endoglucanase enzymes, which break open the structural carbohydrates in plant cell walls. Normally, residue decomposition starts where a stalk has been cut or broken. Opening the cell walls gives the soil’s own microbes many more places to start.
“What typically might take 6 months with a bacterial product should take less than 6 weeks with an enzyme,” Sowder says.
He says the enzyme’s narrow target is what makes it tank-mix friendly. “It’s like a lock and a key. It only works on certain things, so we know it doesn’t have effect on herbicides and insecticides and things like that.” It is also crop-safe, he says: “The enzymes don’t move through the cuticle of an actively growing cell. On dead tissue, it works fine.”
Fall application is possible, especially farther south or after a post-harvest burndown. Spring timing is tighter, but there’s usually a pass to ride with. “It’s a flexible application that’s meant to fit the way you farm,” Sowder says.
Return No. 1: Steel that works
For many operators, the first return is simply equipment that runs cleanly through the field.
Sowder says a digester can set the stage for a smoother planting pass, less need to clear root balls from the planter toolbar.
Residue that is partly digested by planting, even if it hasn’t disappeared, “means that your steel can move it, it can slice it, you eliminate the hairpinning, you have consistent depths,” he says.
Sowder points to operators in high-yield environments where making 3 and 4 tillage or seedbed prep passes on 350 bushel corn is sometimes necessary.
“I’ve [got] guys in that camp that have told me, I just want my steel to work better,’” he says.
Diesel adds to the case.
“Diesel prices are going to be an issue this fall,” Sowder says. “I’m not telling you you can stop tilling. But maybe this would help you at least make sure your steel works even better.”
Whether a digester lets an operation drop a pass entirely is “a case-by-case question,” he adds.
Sowder admits this return is hard to put a number on, but the real value shows up in the details of each operation:
“I want to be able to drive this speed. I want to be able to not wait an extra 4 hours in the morning when I’m planting, because there’s dew on the straw,” he says.
Return No. 2: A stand that returns the whole acre’s investment
The second return is in the evenness of the stand. Mosaic says it has seen up to 5.4% more corn emerged and up to 6.5% more soybeans emerged when the product went out at least three weeks before planting. And he adds the value goes well beyond saved seed.
“Every time you can get additional seed out of the ground, it’s not just seed cost you’re saving. It’s also the potential for yield because of uniformity,” he says. “Uniform fields without gaps in the stand also offer us an opportunity to improve nutrient use efficiency. So for all the things you make as an investment on your acre, a uniform, early emerging crop is key to getting all of your money back out of that acre.”
Return No. 3: Nutrients, and why you can’t have everything
The third return is where timing forces a choice.
Digesting residue releases nutrients, mostly nitrogen and sulfur.
“Both of those elements exist as anions. They have a negative charge, and that means they move through the soil profile fairly quickly,” he says. “If you put this out in the fall, or 6 weeks ahead of planting, any nitrogen or sulfur that’s there, it’s probably not going to be as available when your crop is in place.”
An early application helps field operations and may lose the nutrients. An at-planting application reverses that.
“If we go out at planting, sometimes we have the opportunity to improve the catch,” Sowder says, meaning “the nutrients show up in the crop, but we didn’t get the operational efficiency that we wanted from digesting the residue.”
His example is double-crop soybeans.
“If you’ve got enough moisture to plant a soybean crop, what are you gonna do to that stubble? You’re gonna come hit it with a burndown, right?” he says. Add the digester to that burndown and “you didn’t get any advantage from that straw being moved out of the way for your no-till drill. … But you get the advantage of [Enzara] working to release the nutrients into that soybean crop.”
The data behind this use is thin, and Sowder says so. “We have minimal data set. A couple of bushels out of about a dozen double crop trials last year.” He is also clear about what it isn’t: using the product to replace fertilizer is “not yet” on the table.
The bigger bet: biologicals that stack
Mosaic is testing how Renuvis Enzara works alongside other biologicals, including its own PGPR (plant growth-promoting rhizobacteria) products, with harvest results due this fall. “It has a different mode of action. And I think used in tandem, can have even greater benefit,” Sowder says. “Meaning, 1 plus 1 is 2, or more.”
He frames the pitch as a numbers question, not a luxury purchase.
“It is numbers on a page, and you can’t overspend,” he says. Biologicals, he argues, are “not really the luxury item we’re talking about. They’re really something that enables farmers to be more efficient.”
