In dryland farming, stored soil water is an essential source of water for crop production. The amount of water available for storage and crop use in a particular soil in hillslope topography is affected by its position on the landscape. The effect of slope aspect and position on soil water and its changes throughout the year in dryland farming were studied in southeast Nebraska. North, south, and east‐facing slopes of Wymore silty clay loam (Aquic Argiudolls fine, montmorillonitic mesic) were selected for study. Four positions on each slope including summit, shoulder, backslope, and footslope were identified. Water content of the soil from 0 to 150 cm depth in 30 cm increments was measured weekly by neutron scattering for 2 years. Daily precipitation was recorded. Twenty percent more water was available in soils on the north‐facing slope than in soils on the south‐facing slope at planting and throughout the year. Soils on the east‐facing slope were the driest. They contained 50% less available water than did those on the north‐facing slope. Within slope positions, soils on the footslopes and backslopes contained an average of 4 cm more available water than soils on the summits and shoulders. Soil water sampling at planting time for crop management and yield prediction models should be done according to slope position.

The effect of landscape position and slope aspect on soil water recharge under dryland farming was studied in southeast Nebraska. North, south, and east‐facing slopes of Wymore silty clay loam (fine, montmorillonitic, mesic Aquic Argiudoll) were selected. Four positions were identified on each slope, namely, summit, shoulder, backslope, and footslope. Water content of the soil from 0 to 150 cm depth in 30 cm increments were measured weekly by neutron probe for 2 years. Daily precipitation was recorded. Soils of the north‐facing slope were 10 % less efficient in recharge of available water than soils on south‐ and east‐facing slopes during all recharge periods. Soils on footslopes were 6 to 8 % more efficient than other positions throughout the year. Water storage efficiency of the soil appeared to be higher in fall than in spring. Available water recharge was 9 % more efficient during the fall than during the winter‐spring period in all soils regardless of slope aspects and positions. High correlation coefficients (r) existed when soil available water was related to rainfall in either fall or spring recharge period.

The effects of slope on soil water storage and other water balance components under center‐pivot irrigation were studied in Gage County, Nebraska. Soil water, surface runoff, precipitation, and irrigation were measured for soils of low infiltration on slopes of 2, 4, and 8% under corn (Zea mays L.). Evapotranspiration was calculated. Soil water content (0‐ to 137‐cm depth) during the growing season was higher in soils on 8% slopes than in soils on slopes of 2 and 4%. Runoff from all slopes was not associated with sprinkler irrigation in the crop production system studied. As slope increased, surface runoff caused by rain increased, and internal drainage beyond the 137‐cm depth decreased at approximately the same rate. The overall water depletion during the growing season was not significantly affected by slope.

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