Table S7.

Row-crop fields targeted for prairie strips in Iowa by USDA Natural Resource Conservation Service MLRA slope class and relevant land-use categories

MLRA code*	MLRA name	No. fields	Field area, ha	Mean percent of fields with 4–10% slope
102C	Loess Uplands	1,229	49,034	51.0
103	Central Iowa and Minnesota Till Prairies	9,066	474,780	33.4
104	Eastern Iowa and Minnesota Till Prairies	15,216	652,107	47.3
105	Northern Mississippi Valley Loess Hills	6,969	264,933	54.4
107A	Iowa and Minnesota Loess Hills	8,173	322,946	52.5
107B	Iowa and Missouri Deep Loess Hills	19,906	857,339	47.6
108C	Illinois and Iowa Deep Loess and Drift, West-Central Part	16,329	640,410	49.6
108D	Illinois and Iowa Deep Loess and Drift, Western Part	10,149	411,080	53.2
109	Iowa and Missouri Heavy Till Plain	5,379	233,842	47.5
115C	Central Mississippi Valley Wooded Slopes, Northern Part	189	9,407	37.1
Total		92,605	3,915,879

Fields have at least a 10-ha area with 4–10% slope.

^*USDA Natural Resources Conservation Service (2006) Land Resource Regions and Major Land Resource Areas of the United States, the Caribbean, and the Pacific Basin (US Department of Agriculture). Available at https://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_050898.pdf.