<b>Data from: </b><b>Soil Responses to Inclusion of Corn, Soybean, and Cover Crops under Rainfed Conditions in the Northern Great Plains</b>

Increased prevalence of corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] throughout the northern Great Plains has impacted the delivery of ecosystem services from agricultural lands. Such service-related impacts are often manifested through alterations in soil properties and processes. A study was conducted to quantify the impacts of crop rotation and tillage on a suite of soil properties near Mandan, ND USA, six years after rotation treatments were updated to include corn, soybean, and annual forages (i.e., full-season cover crop mixture). Crop rotations included spring wheat (Triticum aestivum L.)–soybean, spring wheat–corn–soybean, and spring wheat–corn–cover crop each split by no- and minimum tillage. The cover crop was comprised of spring triticale (Triticale hexaploide Lart,), millet [Setaria italica (L.) Beauv.], canola (Brassica napus subsp. Rapifera), sunflower (Helianthus annuus L.), forage pea (Pisum sativum L.), soybean, and pasja turnip (Brassica campestris spp. L.). All crop phases in each rotation were present every year and treatments were replicated three times. Soil samples were collected in 2018 with a hydraulic probe to a 152.4 cm depth in increments of 0-7.6, 7.6-15.2, 15.2-30.5, 30.5-61.0, 61.0-91.4, 91.4-121.9, and 121.9-152.4 cm. Separate samples for aggregate stability analysis were collected with a trowel from the 0-7.6 cm depth. Soil samples were evaluated for soil bulk density, water-stable aggregates (WSA), electrical conductivity, soil pH, nitrate-nitrogen, available phosphorus, sulfate-sulfur, exchangeable cations (Ca, Mg, K, Na), micronutrients (B, Cu, Fe, Mn, Zn), total soil nitrogen, total carbon, inorganic carbon, and particulate organic matter (POM) carbon and nitrogen. Particulate organic matter (POM) was estimated from material retained on a 0.053 mm sieve analyzed for carbon and nitrogen content by dry combustion. Analyses for POM and WSA were conducted for the 0-7.6 cm depth only. Data may be used to better understand soil property responses to crop rotation and tillage practices under rainfed conditions within a semiarid continental climate. Applicable USDA soil types include Temvik, Wilton, Grassna, Linton, Mandan, and Williams.