New opportunity for fall application

The increasing use of fungicides and other products applied late in the growing season has kept many ag planes in the air longer. Now, new technology promises to extend the aerial application season even longer. AgAir Update has learned of a new product that can be applied aerially that few, if any, have considered; simply put, accelerated decomposition of stubble.

The trouble with stubble and other crop residues is it can present a big problem for the grower. Everyone knows crop residues help protect soil by preventing soil erosion during rain events or high winds and replaces some lost nutrients. However, too much residue causes problems when planting, cultivating and can even damage expensive tractor tires. Residues also tie up nutrients, prevent good seed contact with the soil and harbor insects and plant diseases. The faster residues breakdown, the less remaining in the spring and fewer problems for the grower. This is where the airplane shows up.

Not many can argue against crop residue being a problem. It is worse today. The use of foliar fungicides and insect resistance traits have increased stalk strength and slowed decomposition. Primarily, crop residue is a problem in corn. However, many other crops accumulate enough residues to cause problems, particularly in low spots where water flow causes residues to accumulate.

To best understand how the ag-operator can benefit from stubble management and help his customers at the same time, it is necessary to discuss the process. Stubble management is a great concept – breaking down crop residues that cause problems and turning them into an asset by releasing tied up nutrients. High production farming is putting tremendous pressure on soils. Crop residue management is one of the important tools in farming that improves soil quality.
Deep plowing and burning are historical practices farmers have used to manage crop residues. Those practices are labor intensive and both have significant environmental issues and can increase the loss of topsoil. The trend is to reduce use of both deep plowing and burning.

Farmers also use mechanical shredding. Making crop residues smaller helps, but those residues still contain cellulose and lignin that need specific types of microorganisms to breakdown.
An important part of crop residue management is increasing the microorganism populations. Some farmers spray sugars, spread manure and other nutrients in an effort to feed these microorganisms. This is good, if these products actually get into the right place where microbes are present. Unfortunately, it often takes a long time for existing microbe populations to build up to sufficiently high levels on aboveground crop residues.

Up to now, everything written in this article is well-known, common sense farming practices that typically do not include the need for the aerial applicator. These practices are conducted when most aerial applications are at a low point, or stopped, for the season. Should ag-aircraft to get involved in crop residue management, it could be a boom as significant as the great fungicide applications boom.

AgAir Update is being told by GarrCo Products of a new biological technology that is promising to deliver results that could lead to a revolution in crop residue management. These biologicals are highly concentrated with the right type of microbes to degrade tough crop residues, including cellulose and lignin, much better than current nutrient supplements. The microbes in this new product have been specifically selected to digest a diverse range of dead plant material, while leaving living tissue untouched.

Another benefit observed in some field trials is reduced volunteer corn germination. The microbes can act on the seed coating of unwanted corn and weed seeds on the soil surface and reduce their germination. No worries, it will not affect freshly planted crop seeds.

Applying with a little nitrogen, or other nutrient, is a good idea, as it will help kick-start the residue breakdown process until the nutrient producing microbes start fully functioning. This kick starting can be especially important in the fall when the amount of time is limited for microbes to act before temperatures get too cold.

Healthy populations of the right microorganisms to breakdown crop residues will give a continual release of nutrients throughout the growing season and increase yields from single or split fertilizer approaches requiring less total N applied.

The current approach to manage crop residues is to spray residue management technologies directly on the crop residues after harvest, usually as a ground application with fall chemicals. Since chemicals and microbes do not move much on crop residues, their efficacy depends on the spray covering as much of the residue as possible. Adjuvants do help get these products uniformly deposited on the exposed residues, but there may be a better way.

An innovative approach to improve crop residue management is to make an early application of a biological just before harvest (yes, pre-harvest). That timing takes advantage of warmer weather to accelerate microbe growth and uses the harvesting process to mix the microbes on the residues. This application timing is ideally suited for aerial application, not only because of crop size, but the distribution of the biological in a mature crop is a perfect prescription for the airplane, just before the crop enters the harvester.

John Garr tells AgAir Update, “GarrCo’s new biological product, Digest, has been in test trials for three years. We have monitored its use and consistently see, visually, better decomposition of crop stubble at planting. We know this, along with the introduction of Digest’s microbes, the grower is going to have higher yields because of a better planting environment and higher N levels in the soil.

“We see this as a big boom for the aerial applicator. When applied at Digest’s optimum time, pre-harvest, this invites growers to call his aerial applicator to do the job. It is a relatively low volume application mixed with water and/or nitrogen. And, it is very inexpensive for the grower and it pays him back many times over in crop yield.”

Evidently, biological crop residue management is a new, late application opportunity that can keep ag planes flying longer. GarrCo Products has always been a proven leader in spray adjuvants. With its introduction of Digest, aerial applicators should be just as confident on its effectiveness as with all GarrCo Products.

For more information, contact John Garr at (765) 395-3441 or

Write a Comment

view all comments

Your e-mail address will not be published. Also other data will not be shared with third person. Required fields marked as *