One of the most promising conservation practices aerial applicators can assist farmers with is cover crops. Cover crops are grasses, legumes, small grains and other low-maintenance crops planted specifically to improve soil health and biodiversity. By sowing the seeds aerially with a preharvest cover crop application, cover crops control erosion, retain and recycle soil nutrients, build organic matter to improve soil health, improve water quality and moisture availability, and break disease and insect cycles
 

Quick growing cover crops hold soil in place, protecting against erosion from wind, rainfall and snowmelt. By slowing erosion and run-off, this in turn helps protect water quality by reducing sediment in streams, rivers and lakes.
 

Soil health is improved as decomposing cover crops add natural nutrient compounds to the ground, including nitrogen. Subsequently, this reduces the need for future nitrogen fertilizer applications, lowering the production cost of cash crops and reducing fertilizer runoff. Reducing the need for fertilizer makes cover crops ideal for improving soil health over a large area.  Aeri applicators are uniquely qualified to help farmers seed cover crops in this regard, due to the speed and precise timing of aerial application and longer timeframe an aerially applied cover crop has to grow, aerate and contribute natural nutrients and moisture to the soil.
 

While there are several methods of seeding cover crops, aerial application is the most effective means of applying cover crops successfully. The best time to apply many cover crops is when the harvestable cash crop is still standing. Aerial application offers the ability to spread the cover crop seed over the existing crop without any disruption to the standing crop. This means the cover crop can already be established when the cash crop is harvested. Using a drill to plant cover crops requires a terrestrial vehicle and for the grower to wait until their cash crop is out of the field, which might not be the best timing for establishing a healthy cover crop. This can be especially true in northern parts of the U.S. where the first frost can interfere with cover crop growth if they are seeded too late. Aerial application can also be used when the soil is wet and can seed many acres quickly. As timing is a critical part of successfully establishing a healthy cover crop, it is clear that aerial application offers benefits over all other methods of seeding cover crops.
 

The roots of cover crops increase water-holding capacity, reducing susceptibility to drought. Leaves of cover crops provide shading, which can help control the rate of evaporation from the soil. Per the Plant and Soil Sciences eLibraryPro, under a well-developed crop canopy “the initial evaporation rate for a wet soil surface will be lower and the surface will dry much more slowly.”
 

Biodiversity
Cover crops also increase biodiversity by providing food and habitats for natural pest enemies, as well as attracting pollinators. They also release compounds such as glucosinolates that suppress soil-borne pathogens or pests. Many cover crops can also be used as food for grazing livestock. Additionally, cover crops compete with weeds that would otherwise grow unchecked. Increased seeding rates (1.5 to 2 times normal) ensures the crop canopy closes rapidly, improving weed competitiveness.
 

Reducing Soil Compaction
The roots of the cover crop improve soil structure by creating passages that allow for increased moisture and aeration. Soil compaction is essentially eliminated when seeding is done with aerial application.
 

Additional Resources
USDA’s fact sheet on cover crops can be found at AgAviation.org/Files/USDACoverCrops.pdf.
Aerial applicators who want to learn more about how to successfully seed cover crops can watch an on-demand webinar on the topic at AgAviation.org/covercropwebinar