Measuring subirrigation efficiency and uniformity on two subirrigated fields in the Red River Valley

Although subirrigation has proven to be effective in supplying water to crops in Red River Valley, no research has been done to establish the water use efficiency (WUE) and/or uniformity coefficient (UC) for this practice. This project helps quantity the benefits of subirrigation, and shows its effectiveness in supplying water throughout the soil profile, both vertically and horizontally.

There are two SI experimental sites used for this project, one in Richland County, ND and the other in Clay County, MN. The Richland county site is 116 acres with two separate gravity-fed subirrigation system of 4 inch laterals installed at 0.23% grade and 30 ft spacing. The Clay county site is 150 acres with a gravity-fed subirrigation system of 3 inch laterals installed at 0.1% grade and 40 ft spacing. The WUE is determined using in-field soil sampling and in-lab soil moisture determination method. The department faculty, research specialists and students carried out the tedious soil sampling in two fields before and after subirrigation in July and August, 2014.

Left to right, ABEN students Megan and Hannah collected soil samples in a corn field.