1. USDA‐ARS Cropping Syst. and Water Quality Res. Unit Columbia MO 65211 USA
2. Dep. of Agronomy, Horticulture, and Plant Science South Dakota State Univ. 1148 Medary Ave. Brookings SD 57007 USA
3. McCain Foods 1, Tower Lane Oakbrook Terrace IL 60181 USA
4. Dairyland Laboratories 117609 Forward St. Stratford WI 54484 USA
5. Dep. of Agronomy Purdue Univ. 915 W State St West Lafayette IN 47907 USA
6. Formerly Corteva Agriscience current address 13801 Summit Drive Clive IA 50325 USA
7. Dep. of Agronomy and Horticulture Univ. of Nebraska‐Lincoln 202 Keim Hall Lincoln NE 68583 USA
8. Dep. of Soil, Water, and Climate Univ. of Minnesota 1991 Upper Buford Cir Falcon Heights MN 55108 USA
9. Dep. of Soil Science North Dakota State Univ. Fargo ND 58105 USA
10. Dep. of Soil Science Univ. of Wisconsin‐Madison 1525 Observatory Dr. Madison WI 53706 USA
11. Corteva Agriscience 8325 NW 62nd Ave. Johnston IA 50131 USA
12. Dep. of Crop Sciences Univ. of Illinois at Urbana‐Champaign 1102 S Goodwin Ave Urbana IL 61801 USA
13. Dep. of Agronomy Iowa State Univ. 716 Farm House Ln Ames IA 50011 USA
14. Agoro Carbon Alliance 6807 Ridge Rd. Lincoln NE 68512 USA