When Roger Van Ersvelde installed Pow­eshiek County’s first bioreactor on his farm, it was just his latest conservation effort since he and his wife, Louise, returned to farming in 1970.

Van Ersvelde sees good conservation practices as part of what it means to be a farmer: “A professional farmer needs to be a steward of the land. My intention when I quit farming is to leave my farm ground better than when I started.”

For him that means improved soil health, better erosion control, and better water quality, including better removal of nitrates in the water flowing from his farm’s system of tiles. 

Van Ersvelde has a long list of investments he has made in conservation improvements.

“When I got out of the Air Force and came back to farm with my father, we were still moldboard plowing. As we evolved and he left the operation, I started putting more tile in the ground and doing grass waterways so they were all well-shaped.

“Currently, we’re using a mix of mulch till and no-tillage, and obviously we’re soil sampling and using variable rate application for our nutrients.”

As a result, he says, “We’re getting a lot better at when and how we apply nutrients to the soil.”

Working in the terrain

His conservation measures target the challenges of a rolling terrain — some B and C slopes and even some Ds.

“We’ve got some ground that isn’t level by any means,” he says. “I’ve got probably a dozen to 15 water control structures, so if we do get erosion, we’re catching it and taking a scraper to put it back up on the ground where it came from.”

GPS and other technologies have helped the Poweshiek County Farm Bureau member target his conservation investments.

“It’s been a good investment even if it’s caused me to spend a lot on tiling, waterways and other structures,” he said. 

Van Ersvelde sees the bioreactor “the next logical step” to address nitrates coming off the farm.

The bioreactor is a large trench filled with wood chips and covered with topsoil and perennial grasses.  Van Ersvelde’s reactor is 16 by 64 feet and sits slightly lower than existing tile lines. Water from the tiles is diverted into the wood chips, where microorganisms convert nitrates in the tile water into nitrogen gas. The gas is released into the atmosphere, while the cleaned water flows from the end of the chamber into downstream waters.

The bioreactor was a “fairly significant” investment, he says.

“So right now, we’re kind of sitting still to see how it comes along. If it’s very effective, then we’ve got some places where we could put bioreactors on our south farm.”

Spreading the word

Van Ersvelde’s commitment to conservation reaches beyond his farm investments to help other growers. He works with the Little Bear Creek Watershed Improvement Project on water testing, hosts field days and interested groups on his farm, and serves as an assistant county soil commissioner to share his expertise.

“Sometimes you’ve got to be patient and look at what the long-term benefit is going to be for the ground you’re farming. Because if you only look at the short term, it can seem like a lot of investment,” he said. “Conservation is very important to the farm, to the economy, and to the world, and farmers need to be involved in those efforts.”

Munro is a freelance writer in Des Moines.