On the Delmarva Peninsula, where every pound of fertilizer applied is regulated, Maryland farmer Temple Rhodes is rebuilding his corn production system from the ground up — literally.
“We are in the Chesapeake Bay watershed, so all eyes are on us,” Rhodes says. “I am 50 miles from Baltimore, 50 miles from D.C., 67 miles from Philadelphia. We are in a hotbed of regulation.”
For the past 25-plus years, Chestnut Manor Farms has operated under a state-mandated nutrient management plan that caps how much nitrogen and phosphorus can be applied. Rhodes says participating in the program is not voluntary.
“It is forced on us with no incentive. You just have to do it,” he says. “So, we have to reinvent ourselves. We have to start looking at other ways to do things.”
Rhodes grows corn, soybeans and wheat, along with a few acres of grain sorghum. He also runs a cow-calf operation and backgrounds a couple hundred head of steers each winter on cover crops. The diversity helps, but the real transformation is happening in how he feeds his 1,700-acre corn crop.
From Front-Loading To Spoon-Feeding
For years, the standard practice was to front-load fertilizer before planting and hope enough stayed in place through the growing season. Under tighter rules and scrutiny, Rhodes says that approach no longer works.
“We used to put 100% of our nitrogen up front, then plant a crop on it and expect it to be there all along,” he says. “That is where we find out we are making a mistake. We are limited in how much fertility we can put on, so we better get it on at the right time, in the right place, or we are going to run out.”
Today, Chestnut Manor relies on what Rhodes describes as a systematic, layered approach that can include planter-applied fertilizer (in-furrow and 2x2 programs), split in-season applications of nitrogen, extensive cover crops and biologicals.
“When you take a systematic approach to all these things, it becomes a different animal,” Rhodes says.
Most of his corn is grown using a strip-till system with strips built in the spring. State rules prevent him from applying fertilizer in the fall, so he must work ahead of the planter using modest rates of nitrogen and then follow up with in-season applications.
“My end goal is to grow 225 bushels per acre,” he says. “I am going to put about 0.7 pounds of nitrogen per bushel on my crop. I can get away with that if I spoon-feed it correctly. If I put it all down up front, I am going to need about 1.25 pounds. I’m saving a lot of fertility by doing it this way.”
Rhodes says Maryland’s regulatory framework ensures he stays within strict application limits. The state’s phosphorus usage tool combines soil samples, yield history, location and soil type into an algorithm that dictates what farmers can apply.
“You put your soil samples in, you put your yield goal in, and it spits out what you can put on,” Rhodes says. “If you say your yield goal is 250 bushels but your APH is only 180, that is not how it works. Your APH and your yield goal have to be very similar, or you are not going to get to put on what you want. They are going to tell you what you can put on. Period.”
A New Technology Takes Root
Working under those constraints, Rhodes has become aggressive about testing new technologies that promise better nutrient efficiency and stronger root systems. Not one to be painted into a corner, Rhodes stays open to all ideas of what could work within the state’s mandated parameters. One of those is a biostimuant from NewLeaf Symbiotics.
The product is a non-GMO, naturally occurring bacteria known as PPFMs (Pink-Pigmented Facultative Methylotrophs), often called “M-trophs”. The PPFM-powered biostimulant is designed to improve crop yield, nutrient uptake, and stress tolerance, according to NewLeaf.
In the process of trialing the product, Rhodes shared the technology with XtremeAg, a group of seven farmers across the country who rigorously test new technologies in different environments.
“If we can test a product at multiple locations — a guy from Iowa, a guy from Maryland, a guy down South — and it works across everybody, that is big,” Rhodes says. “It is huge, because what works for me might not work for the guy in the Midwest. It all goes back to soil type and environment.”
Rhodes says what he was looking for from the biostimulant was stress mitigation and nutrient scavenging that can improve his current foundation for the future.
“I need a massive root system that can go out and get more nutrients, because I am limited on how many nutrients I can put on,” he says. “If I build a plant that scavenges more, that is a home run for us.”
Cutting Irrigation And Boosting Biomass
Rhodes farms a mix of acres, with about 25% irrigated and 75% dryland. After the first year of trialing the NewLeaf technology he found he didn’t need to run his irrigation system as frequently.
“The root system and the plant that it makes, I do not have anywhere near the stress,” he says. “When it’s hot and dry we would normally run the irrigation system, but I found I do not need to put on as much water.”
With irrigation costing about $125 per acre, every pass he eliminates adds up to a significant savings.
“If I make 12 passes a year, I can save $10 an acre just by not turning it on one time,” he says.
Beyond water savings, Rhodes estimates he is getting 30% more biomass in the plants.
“We actually cut corn stalks off at the ground and weighed them. We did not even measure the roots — just the plant itself. Thirty percent more biomass than my grower standard practice,” he says.
The biomass offers a payoff for grain production and nutrients for his cattle operation.
“I chop silage, so if I can add 30% more, that is 30% fewer acres I need to chop,” he reports. “It costs me by the acre, so 30% less is massive. And the nutrients in that plant are higher than in my grower standard practice. It all follows each other.”
Learning Curve And Next Steps
While the product delivers more biomass and higher yields, it did create new management challenges. Rhodes discovered the downside of building a much bigger plant on a tight nitrogen budget.
“In my system, I put about 30% of my nitrogen needs down with my strip till. I plant on top of it, everything looks great, it makes this massive system — and then I end up running out of nitrogen later in the season,” he recalls.
He spotted the problem at harvest, with many ears showing considerable tip-back of an inch or two. Rhodes figures the crop just “outran” his nitrogen program. Even so, the fields containing the experimental treatment still out-yielded his standard fields by an average of 11 bushels per acre.
The experience pushed him to rethink nitrogen application timing and total rate.
“I’m pulling some of the front-end nitrogen out and putting it into reproduction, so I do not run out at the end,” he says. “Instead of 0.7 pounds per bushel, maybe I can go to 0.8 or 0.9, maybe even one-to-one, and still be efficient because of what this product is doing.”
The results from the past two years of field testing are strong enough that Rhodes is no longer treating the technology as a small trial.
“We plant about 1,700 acres of corn, so it’s going on every acre of corn,” he says.
On a tightly regulated farm in the Chesapeake Bay watershed, Rhodes is betting that bigger roots, smarter fertilizer use and careful experimentation with nutrients will keep his operation profitable — all while staying within the rules.
