This project monitors the movement and loss of nitrate-nitrogen in an agricultural field recently converted from managed timber to irrigated row crops. This is the first study of its kind in the state, and perhaps nationally, to begin studying groundwater impacts from irrigated agriculture the first year of production.

This unique long-term study began the first year the land was converted and will help researchers, agricultural industry and government agencies better understand the potential groundwater quality impact of such land use transitions. Study results are informing researchers on the most advanced and beneficial agronomic practices to minimize the movement of nitrate beyond the root zone.

A timeline of activity for the Byron project. Before 2013: Potlatch Corporation Harvested Timber. 2013: Final tree harvest, land prepped. 2014: Soybeans planted, lysimeters installed, irrigation water use permit approved, drain gauges installed, monitoring wells installed. 2015: Corn grown. 2016: Soybeans grown. Fall 2016-2017 Rye grown. 2018: Peas grown. 2019: Soybeans grown. 2020 Barley grown. 2021 Soybeans grown. 2022 Oats grown. The project is located in Byron Township in Cass County in central Minnesota.

 

Background

The potential for groundwater impacts by nitrate-nitrogen in Minnesota's Central Sands region is considered high. Water moves quickly through the region's sandy soils and can easily carry nitrate-nitrogen from fertilizer and decomposed organic matter into the shallow groundwater.

The conversion of managed timber land to irrigated cropland in Minnesota's Central Sands region has occurred over the last several years following changes in land ownership. The study site for this project is located in Byron Township, Cass County, 12 miles north of Staples, Minnesota. The 160 acre site, known as Byron #1, has loamy sand soils and groundwater that occurs at depths of 10 to 20 feet.

Key Study Components 

Scientists are using a combination of monitoring methods and key study components to understand the dynamics of water movement and level of nitrate in the soil and water. Preliminary results show nitrate-nitrogen concentrations from Byron #1 measuring in a range comparable to or less than other locations using a corn/russet/bean rotation.

Farming Practices

The farming operation is shared between the landowner and Central Lakes College.  Due to the high risk of groundwater contamination, the landowner and Central Lakes College continue to develop and implement innovative cropping and other farming practices to reduce nitrate loss.

Partners 

A unique collaborative team leads this project. It is an example of landowners working with government agencies, institutes of education, businesses and a farming association to better understand the impacts to groundwater.