Spring planting is several weeks away. However, planters will soon be coming out of hibernation for preplanting maintenance. This is a good time not only to get the planter in top condition, but also to think about considerations for planting into cover crops. The following recommendations come from Mark Licht, Iowa State University Extension Cropping Systems agronomist.

Planting corn or soybeans following a cover crop is not business as usual. Even farmers who have been planting no-till for a long time indicate planter settings must be adjusted. The same criteria need to be met whether planting into cover crop residue, high-residue, or low-residue situations.

Focus on attaining optimal seed depth, make sure the seed furrow remains closed, and reduce risk of compaction from too much row-unit down-pressure and sidewall smearing. This sounds easy and straightforward; however, often planting into cover crop residue fails for these reasons.

Avoid sidewall compaction
Sidewall compaction occurs because cover crop residues reduce soil water evaporation, increasing the time needed for soil drying prior to planting after spring rains. Shallow and variable seed depth is due to lack of row-unit down pressure, while too much down pressure creates a compacted zone beneath the depth gauge wheels, potentially resulting is poor root development. Seed furrows can reopen as a result of not enough pressure on the closing wheel.

Knowing when soil conditions are ready for planting requires taking the time to check soil conditions. Remember, it’s not what the surface soil conditions are, it’s the soil conditions where the seed is placed. Make sure double-disk openers on the planter still have a bevel and have 1.5 to 2.5 inches of contact.

Row-unit downforce should be enough to place the depth gauge firmly in contact with the soil, yet should allow it to be turned by hand. Closing wheels should be checked to make sure the furrow closes again. In wet soils, too much pressure on the closing wheels cause problems.

Conservation Q&A
In other conservation news, a new column in the monthly online newsletter from Iowa Learning Farms explores questions related to crops and conservation, providing answers and resources for more information. If you have a question you would like to have answered about a conservation practice, soil health, water quality or other related topic, submit it to [email protected]. Here’s a Q&A from this month’s ILF newsletter:

Q: What is the cost difference between drilling and aerial overseeding cover crops?

A: With tight commodity budgets, it is important to evaluate prices of different species and seeding methods. ILF has an easy-to-use cover crop cost calculator tool that calculates the cost of drilling and aerial-seeding cover crops for quick comparison. Try the Seed Price Calculator Tool.

The downloadable Excel file calculates the total cost of using the cover crop including seed, application and chemical termination. You can use the calculator for a single cover crop species or up to six species to a mixture. To use the calculator, download and open the Excel file (Microsoft Excel software must be installed on your computer in order to use the file). Any cell that is shaded in yellow can have a value inserted, including the cost of the seed in dollars per pound and cost of application.