News from Your Federated Agronomists | July 9, 2019
cover crop2015
Good Cover Crops Add Future Crop Value to Prevent(ed) Plant Acres
For growers who were unable to plant corn and/or soybean crops this year, there are a number of cost-effective options that are beneficial to future crops, according to Kevin Carlson, Federated’s agronomy sales manager. 

Because unplanted fields quickly become weed beds that demand tillage or herbicide applications, cover crops are a valuable option; they can “suppress weeds, offer ground cover and support soil biology that will improve future crop yields,” said Carlson.

“Fallow syndrome is a phenomenon that happens when the soil is left bare … devoid of plant [non-weed] growth during the year … the soil biology starts to die off … many soil microbes depend on a living plant root host,” said Carlson.

One of these important soil fungi is mycoryzea; it helps crop plants find more phosphorous and zinc in the soil. These microbes are a massive extension of the plant root, but they start to die back when there is no crop/cover crop to help them survive. 
To make the best cover crop choices, consider the following:

Start by checking insurance coverage guidelines.

Carlson noted – as described in this audio – crop insurance release dates for forage have changed on prevent plant acres. Make a call to the insurance company before deciding on prevent plant options. The UMN Extension service provided this list of forage crop possibilities.

Know the advantages of keeping living roots growing after small grain [cover crops] have been harvested. The roots:
  • build soil organic matter (which will increase crop productivity in the future);
  • capture soil nitrogen and depositing into a future crop;
  • increase water infiltration;
  • armor the soil and reduce soil erosion.

First photo below shows plant biology in play as an earthworm moves through crimson clover roots.
Second photo below shows the nodules on the clover root.
soil biology with earth worm
clover nodules
Choose a good cover crop mix. Carlson recommended this economical mix:

  • Rape seed at 2-3 lbs./ac.
  • Forage radish seed at 1-2 lbs./ac.
  • Crimson clover seed at 3-4 lbs./ac.
  • Berseem clover seed at 2-3 lbs./ac.

Carlson used this mix on his own farm in 2015 when he had cover crops planted behind wheat. “The goal is to have enough seeds per acre to cover the ground 30-60 days after seeding. An 8-10 lbs./ac. seeded rate will accomplish this goal,” he said. See photos below.

In addition to talking to your Federated Agronomist , this Midwest Cover Crops Council decision tool can also help determine cover crop options. Additionally, the UMN Extension provided this list of cover crops with optimum planting dates and suggested rates.

“Losing a year’s cash crop is devastating, but planting a cover crop will help ensure that you keep your topsoil in place and possibly even see some soil improvements in the coming years,” as an early June UMN Extension service report stated.

Know your options and then put them to work to make the best of prevent(ed) plant acres. Talk to your Federated Agronomist to determine what works best for your farm this year.

Photos below:
  1. Inexpensive, nitrogen-fixing crimson clover; usually winter terminates.
  2. Bio-diverse rape, radish, crimson clover mix (2015 season).
  3. Winter terminating tillage radish
  4. Tillage radish tap root for relieving compacted soils
  5. Crimson and rape still green in Nov. 2015
crimson clover
rape radish clover mix
tillage radish
tillage radish in soil
crimson and rape still green in Nov