Soil Root Zone Available Water Capacity: Central Nebraska Loess Hills

This Root Zone Available Water Capacity (RZAWC) map of Central Nebraska Loess Hills is from a collection of interpretive maps illustrating the application of detailed soil survey information obtained from the Soil Survey Geographic Database (SSURGO) for natural resource planning. It is an important tool for making land use and management decisions related to the soil resource.

The RZAWC is the sum of available water capacity multiplied by thickness for all layers in the root zone. This approximates the volume of water held in the root zone that can be used by crop plants. The importance of RZAWC varies somewhat geographically because the capacity to hold water during key parts of the growing season is more critical in some climates than in others. Available water in the surface layer is critical to establish plants, but the amount of available water stored throughout the root zone usually determines the most productive soils.

Courtesy of USDA Natural Resources Conservation Service–National Geospatial Development Center.