Managing Crop Residue at Harvest and Beyond

Putting down an even cover of crop residue protects the soil surface and sets the stage for a healthy seedbed. It all starts with the combine.

By Marilyn Cummins

The stems and stalks from harvest can conserve soil and moisture while recycling nutrients to help feed future crops. How evenly crop residue comes out of the back of the combine is a crucial starting point for how well it protects the soil from wind and rain erosion, while avoiding issues that interfere with planting the following spring.

“The key is setting a residue management goal and then making sure your combine and tillage operations are properly set up to manage residue as expected,” says Jason Lee, North American agronomy and farm solutions specialist for AGCO. Residue that is spread unevenly at the start can lead to several agronomic problems the following year, he says, and you only get one chance.

“With too much residue, soils can remain cool and wet, which may delay planting or slow seed germination in the spring,” Lee says. And too much residue in the furrow can physically interfere with proper seed-to-soil contact and uniform seedling emergence. The 2018 seed-trench residue management trial at the Precision Planting’s Precision Technology Institute at Pontiac, Illinois, showed a yield loss of 1.1 bu/acre for every 1% decrease in a clean furrow. The physical interference of residue over top of the planted row can also block the shoot development of young plants.

Lee says that when residue is unevenly distributed over a field, not only are exposed areas at risk for erosion, but inconsistencies in soil temperatures and moisture also may cause uneven plant emergence the following year, hurting yield. Ideally, he says, “residue should be spread consistently and managed to promote uniform rapid warming and drying in the spring for earlier planting and sufficient seed germination.” It is also important to keep in mind that spreading residue evenly behind the combine also results in an even distribution of nutrient recycling back into the soil.

Leaving heavy mats of residue “bands” behind the combine can also create other problems related to disease and nitrogen management. Overall, residue requires contact with the soil to decompose. Heavy mats of residue with less soil contact therefore will not decompose as quickly. Residue that doesn’t decompose for a long period prolongs the development of several plant diseases that live on residue. Growers who surface-apply urea without incorporating also are at risk for significant N loss in areas of the field where heavy mats of residue exist. Urea fertilizers that land on top of a heavy residue can quickly convert to ammonia gas and volatilize before reaching the soil, leading to severe N loss in those areas of the field.

New Fendt® IDEAL™ Combine Spreads Residue Widely and Evenly

The challenge of spreading crop residue evenly throughout the field is growing as combine headers get larger and larger, says Caleb Schleder, AGCO tactical marketing manager for combines, with some operators running headers as wide as 50 feet. “The main goal when harvesting is that you want the spread of your residue to equal the size of your header,” he says. “That way, we don’t leave what we call ‘hot spots’ in the field with no cover, no protection from erosion.”

When designing the new Fendt IDEAL combines, AGCO built in several key features that benefit operators when it comes to efficient and complete residue management, Schleder says. At the front of the machine, customers can choose a chopping model of the 3300 Command™ Series corn header with point-to-point stalk rolls that “do a great job biting into the stalk and putting it into smaller increments for better breakdown in the soil.”

Behind the head is one of two straw chopper options, either a BaseCut with 56 knives or a ShortCut with 112 knives. Schleder recommends the 112-knife straw chopper for soybean harvesting to produce finer material for easier breakdown. “We have a direct discharge into our chopper, without a beater or any extra components,” Schleder says, for a very simple and effective design.

The chopped residue is then expelled through the IDEAL ActiveSpread tailboard, an AGCO-exclusive option with two turning spinners and eight deflecting tailfins to spread residue evenly and at the full width of any header, even the 50-footers, and even in a crosswind. And it does it while consuming only 3-5 HP, compared to 30 HP for a competitor’s spreader.

“We’ve been in fields where other combines are running that don’t have the ability to compensate for wind,” Schleder says, “And wind, when it comes to residue management, is sometimes a disaster.” With IDEAL, the operator can use the in-cab terminal to set ActiveSpread for wind compensation, and actuators adjust the tailfins hydraulically to keep spreading a full-width swath, even in a crosswind. It even flips the tailfins for you when you turn at the end of the field.

In addition to ActiveSpread, the IDEAL combine features a chaff spreader beneath the shoe that is controlled from the cab to discharge chaff to areas the operator chooses, including at a 90-degree angle to the direction of the combine “to get that spread you desire to prepare yourself for next season and keep your soil healthy through the winter,” Schleder says.

IDEAL Makes Short Work of Green-Stem Soybeans

Seeing is believing, and Conor Bergin, AGCO brand manager for Fendt, saw first-hand how well IDEAL harvested and managed the residue of soybeans with green stem syndrome in the hills of Northwest Iowa this past fall. “We were running a 40-foot draper header, and our residue spread pattern was out past the header itself,” he says.

“I was absolutely impressed with the grain loss, or lack thereof, I should say,” he adds. “We were well under a quarter bushel of loss per acre out of the back of the machine, consistently, in tough conditions. They were high-yielding beans, and we were running at 5 to 5.5 miles per hour.”

He credits the nearly 16-foot-long new dual helix rotors in the IDEAL Class 8 model the customer was running for being gentle on the crop while producing a clean sample. The increased surface area for threshing and separating the crop lets the rotors run at lower speeds, using less fuel and creating less noise even when running at high capacities.

Bergin says that the seven-year process to develop and bring IDEAL to market as a premier product has been a strategic effort to “demonstrate to customers that we can meet their agronomic needs and provide them with a superior return on investment. With the Fendt Gold Star Customer Care Plan, we minimize their variable expenses and reduce risk while ensuring they have maximum uptime during harvest.”