Cover crops field day held in Fillmore County
On a hot and breezy late summer afternoon, a fleet of pickup trucks lines the side of a gravel road one mile south of Milligan, Nebraska. Golden, ripening corn and soybean fields stretch into the distance on all sides as about 40 people follow local farmer Jordan Uldrich into the one section of farmland that looks different from all that surrounds it. Here, a lush growth of cover crops fills the wide space between the rows of corn.
When it comes to cover crops and other soil health practices, “it’s worth trying,” Uldrich tells the audience gathered in his field. This season, Uldrich was trying some things for the first time. With a goal of using less inputs and suppressing weeds, Uldrich used a five-acre patch of dryland corn to experiment.
Uldrich invited producers to view his test plots during a recent field day event hosted by the Upper Big Blue Natural Resources District and The Nature Conservancy. The event drew area growers who were curious about getting started with cover crops on their acres, as well as those who are already implementing soil health practices and are enthusiastic about the results. The field day was an opportunity to see the results of Uldrich’s experiments up close and to ask questions of the grower as well as a handful of staff members from agencies including USDA-NRCS, UNL Extension, Pheasants Forever, the NRD, Nature Conservancy, and the Department of Natural Resources. Participants mostly came from the Upper Big Blue district area, but some came from as far as Sioux City, Iowa. Part of the draw of the event was the chance to network and learn what other producers are doing in the area.
When discussing his motivation for the summer’s experimentation, Uldrich says he “wasn’t trying to win a yield contest,” but rather, he was interested in testing strategies for weed suppression, especially for palmer amaranth, and seeing if there was an economical way to use less chemical inputs while maintaining a profitable yield.
“Nitrogen management is essential to weed management,” said Uldrich, explaining that where you have excess nitrogen, you'll have more weeds. “I'm getting serious about judicious use of nitrogen when we are trying to control weeds.” Each plot had 30 lbs. of nitrogen applied in the spring. On four of the test plots, Uldrich applied 55 lbs. of nitrogen and 20 lbs. of sulfur in-season. The fifth plot had no additional fertilizer applied after the 30 lbs. in the spring.
None of the plots had fungicides or insecticides applied, except for what was on the pretreated, conventional seed. Uldrich added a few different biological products and all five plots were planted into a rye cover crop that had been chemically terminated six days before planting. One plot included a conventional herbicide program in 30” rows with no cover crops. The other four all included an 8-way cover crop mix interseeded at V3-V4, with varied row spacing and nutrient application. The Upper Big Blue NRD assisted Uldrich in planting his cover crop with an interseeder. The land had been no-till for 20 years, however, this was the first season Uldrich had experimented with cover crops.
The cover crop mix on the test plots included forage peas, mung beans, berseem clover, oats, turnips, impact forage collards, buckwheat, and pie pumpkins. It had been fairly dry for the last six weeks prior to the field day, however when Extension Educator Jenny Rees lifted a spade of soil from between the rows among the cover crops, she noted subsurface moisture present, as well as good soil structure.
When it came to pest control, Uldrich noted the grasshoppers were “in the covers, not the corn,” as were the Japanese beetles. “They'd rather chew on the covers. Give them something succulent to chew,” if you want them to leave your primary crop alone, he told his fellow farmers. “The healthier the soil, the more likely you are to have the bugs that will help you.”
Field day participant Don Hilger grows organic popcorn and does custom seeding and seed cleaning. He’s a fan of cover crops for a few reasons. “If you get your nutrients right, it attracts the beneficial bugs, and the bad bugs don't like the sugar content of your healthy plants,” he said. “If you have nitrogen and phosphorus in the soil but don't have the biological activity, you can't access the nutrients." Hilger says he tests regularly through the season to determine which nutrients to add and in what quantity on his acres.
Uldrich’s test plots revealed varying levels of success. Uldrich plans to analyze results after harvest and expand on the most successful practices in the next growing season. He's also considering carbon market influences, including how much carbon the various practices would capture and whether that will offset the cost of some yield loss. He plans to do more acres of cover crops and continue to reduce inputs, utilizing SAP testing to provide a road map for nutrient application in-season.
When it came to the various row spacing, Uldrich suggested there is no one size fits all approach, but that spacing should depend on what you're trying to do. If you have cows that you want to graze on the cover crop, 60-inch rows are ideal. “Cows are the perfect bioreactor on the fields. Buffalo built the soil. The closest we've got now is grazing cattle,” he explained.
If you are looking for weed suppression, 30-inch rows work best. Why is he so concerned about weed control? He predicts that in 10 years we will not be able to control aggressive weeds with chemical means due to herbicide resistance. “I'm trying to get ahead of that curve. Biology has a lot more to do with it than chemicals,” he said. Uldrich plans to plant a rye cover crop this year after harvest as well.
“Have something green out there year-round,” he told his audience. When you do, you'll continue pumping exudates into the soil where the plants can access it, creating an exchange of nutrients.
Uldrich suggested that everyone, “find the back four acres and try something.”
“It's a worthwhile endeavor. If everyone can take one step in the right direction, we don't all have to sprint to the finish line,” he said.
Farmers interested in funding for cover crops and other soil health practices in the Upper Big Blue Natural Resources District can contact Jerod Fling at jfling@upperbigblue.org or (402) 366-5272.
