A relatively early and kind maize harvest has left soils in better shape than last year’s mud bath. However, leaving bare soil over winter is never a good thing as it results in:
• Erosion risk
• Nutrient leaching
• Loss of soil biology due to the absence of living roots
The photos show the tools and results of a very successful undersowing operation. Soil was stabilised, maize yields unaffected and harvest worries of mud and compaction significantly alleviated. The resulting grass provided excellent quality late autumn grazing for dairy heifers.
Sowing a more diverse mixture under your maize canopy would achieve many benefits, particularly if grazing is not an option.
• Radish has deep tap roots which aid water infiltration, scavenge nitrogen and alleviate compaction.
• Annual clovers such as Crimson or Berseem will fix N for the following crop. They are non-hardy, so a following winter or spring cereal crop could be direct drilled into the cover crop without the need for herbicides.
• Phacelia is also non-hardy and an excellent weed suppressor, easily incorporated into the soil.
• Ryegrass and white clover provide a thick but shallow root mat, reducing erosion risk.
• Vetch has good N-fixing potential and is an excellent weed suppressant. Combined with Rye, both are winter hardy so could provide grazing or silage in the following season.
Species choice should be determined by what you want your cover crop to achieve.
With regulation likely to place conditions on maize growing to prevent bare stubbles, and with the new ELMS scheme focussing on techniques such as diverse cover cropping, 2021 is the time to trial a few mixtures and find out what works for your farm.
Contact Tom at firstname.lastname@example.org or your local FCG Office, for more practical information and seed mix options.