As fall harvest season approaches, crop canopies are starting to open and allowing more sunlight penetration into the ground between rows. The additional sunlight will provide an opportunity for aerial seeding cover crops such as oats, wheat, triticale and cereal rye.

Generally, aerial seeding occurs with soybeans when the maturing plants start senescencing, with leaves turning yellow and dropping from the stems.

The upside to aerial seeding is that the cover crops’ fall growth may extend three weeks or more. The downside is reduced seed-to-soil contact compared to drilling seeds into stubble fields soon after harvest. So if there is a lack of surface moisture during aerial seeding, it may require doubled seeding rates compared to drilling as compensation for reduced seed germination. That increases overall cover crop seed costs.

For drought zones, producers may be hesitant to aerial seed or drill until significant rainfall is forecast. While cereal rye has been successfully seeded as late at Thanksgiving, fall growth is dramatically reduced by delayed seeding.

Research indicates that cover crop biomass doubles each successive month that cover crops growth is extended into the fall before temperatures drop.

The establishment of cover crops immediately following corn harvest can be a challenge, especially when corn stover residue is heavy. In some cases, baling corn leaves, husks and stalks will allow better drilling conditions for cover crops. However, this practice is risky if irrigation is not available or droughty conditions prevail.

Also, growing cover crops will improve soil health; since live soil microbes require living roots as their food source. So, even later planted cover crops will provide soil health benefits such as building soil carbon.

During drier falls, cover crop stand establishment is risky especially when irrigation is not available and rainfall & stored soil water are in short supply.

By Todd Whitney

© 2023 The North Platte Bulletin. All rights reserved.