Instead of leaving fields bare after corn silage harvest, adding a living mulch may help no-tillers prevent costly soil erosion and improve soil health.

USDA scientists in Minnesota have found seeding kura clover as a living mulch shows promise as a way to improve dairy profits by growing forage between the rows of no-tilled corn or soybeans. In the off-season, the second crop acts as a living mulch that also improves the infiltration of water and helps warm up the soil. 

Below ground, the kura clover improves soil structure, helps assimilate excess nitrogen and sometimes stores carbon. It also provides nitrogen for the subsequent cash crop.

Trap More Moisture

The researchers found kura clover improves the soil’s ability to absorb rainfall by as much as 10 times over conventionally-planted fields. Used as a perennial cover crop, kura clover doesn’t need to be reseeded every year.

“A living mulch is a companion crop system that provides the benefits of a mulch in annual row crop systems through the use of a low-growing perennial ground cover,” says John Baker, soil scientist and research leader at the USDA’s Soil and Water Management Research Unit in St. Paul, Minn. “We use kura clover, which lives for many years without requiring replanting, and we can plant corn and soybeans into it.”

A major drawback to a typical silage system is that it leaves the soil bare and unprotected after harvest. This can lead to a long-term decrease in soil organic matter because none of the above ground portion of the corn plant is returned to the soil. On the other hand, the living mulch protects the soil surface and provides carbon to maintain organic matter.

Give it Time

“Kura clover puts much of its initial resources into roots and rhizomes, so initially it will look like the weeds have the upper hand,” says Baker. “However, each time it’s mowed, the kura comes back stronger and, eventually, the grower is rewarded with a healthy, vigorous cover crop that can last for decades.”

Baker says a living mulch is an ideal system for no-tillers growing corn silage. It’s a low-cost way to keep the soil covered after cutting corn silage without the time and expense of seeding a cover crop every year.