The dozers were crawling, the scrapers were filling with earth, and a dozen pieces of construction equipment were buzzing in all directions. It was the last week of July 2019, and Kelly Nelson was clearly in awe of the speed and skill at which a new reservoir was taking shape on the 240-acre Grace Greenley farm in the northeast corner of Missouri. “Can you believe these guys can build a lake in a week?” the research agronomist asked.

This was no mirage. Thanks to collaboration with USDA’s Natural Resources Conservation Service and the Missouri Land Improvement Contractors Association (LICA)—along with a list of industry partners—a 13-acre irrigation reservoir took shape in only seven days. This is Phase III of the plan to transform the farm, one of three that make up the University of Missouri’s Greenley Research Center, into a showplace for conservation.

The goal is to transform the farm into a leading-edge research site for holistic drainage water management. That combination of technologies places this property at the forefront of high-yield, resilient crop production. And it becomes a showcase for environmentally friendly practices that address water quality concerns. “Water continues to be the biggest challenge in reducing year-to-year variability in crop yields,” Nelson points out. “We closely track weather, and we no longer see ‘normal’ years.

“We either have too much or too little rainfall. If we have too much moisture, we can lose nutrients in drainage water. That’s money going down the tubes.”

Terrace trials. Typical of north Missouri farms, the Grace Greenley fields represent a combination of slopes and soil types. The first phase for researchers was to establish a project that could provide a detailed look at a terrace system when managed with or without a cover crop between the corn and soybean cash crops. The farm, gifted to the university in 2014, has since been improved  with a series of six parallel terraces. Soil-health measurements taken before construction allow researchers to compare data with subsequent readings at various locations in the system.

The terraces are studied as micro-landscapes; researchers are tracking performance on the terrace shoulders, backslopes, sideslopes, and channels. As expected, early results indicate that best yields occur on the shoulders, with lowest yields in the channels. The combination of terraces and cover crops are giving some encouraging early results. Suspended solids were reduced by 41% in a two-year cumulative study, while nitrate loss was reduced by 52% when cover crops were present. “Cover crops also reduced total discharge by 43%,” Nelson points out. “Cover crops are allowing more moisture infiltration.”

On the edge. The second phase for this research farm involved two edge-of-field practices—a denitrifying wood-chip bioreactor and a saturated buffer. These practices are tied in with a subsurface drainage system on a field with varying slopes, with tile patterned perpendicular to the slope. Designed to remove nitrate nitrogen before it leaves the field, early indications are that these practices are highly effective. Results from early studies show that the bioreactor, for example, has reduced nitrate N from drainage water by 70%.

The crown jewel will be the combination of drainage water management and subsurface irrigation on 33 acres of the farm. A previous long-term study of such a system on another farm boosted corn yields 45% and soybean yields more than 20%. “The holistic approach lets us study a variety of practices,” Nelson says. “We hope to identify systems that fit well with specific landscapes.”    

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