No-tiller Steve Groff of Holtwood, Pa., says he recently grew 190-bushel-per-acre corn on farm-scale plots without the addition of nitrogen.
The tests were replicated in fields that have been continuously no-tilled for 18 years. The test fields were seeded in August 20, 2010 with a 10-species mix of cover crops.
TA Seeds variety TA525-13V (103 day) corn was planted April 29, 2011. No starter or N was applied. Other plots in the fields receive 60, 90 and 120 lbs of N at sidedress. The harvest was measured by TA Seeds' weigh wagon.
For a nitrogen-hungry crop like corn, such results are virtually unheard of in the agricultural arena, Groff says.
Groff worked for more than a decade with Ray Weil at the University of Maryland to develop and market the Tillage Radish cover crop. He says says this year's outcome is attributed to the sustained use of no-till practices over time as a means to build soil health, combined with nitrogen fixing cover crops.
Groff says his research shows that strategically selected blends of the Tillage Radish, legumes like Austrian Winter Peas, and soil-building plants like Phacelia and others can dramatically reduce or — in some cases, like with this research finding — replace the need for additional fertilizer input altogether.
Cedar Meadows Farm covers 215 acres in Southeast Pennsylvania, just a few miles north of where the Susquehanna River empties into the Chesapeake Bay.
Groff's recent annual Cover Crop Field Days attracted hundreds of farmers, scientists and environmental proponents to see how cover crops are used to virtually eliminate soil erosion, reduce the use of pesticides, enhance soil biology and increase yields.