National Drought Mitigation Center

Plant Growth per Inch of Moisture

Seasonal growth patterns in the Great Plains correspond to precipitation regimes.

How much forage will pastures produce per inch of moisture?

Information from the NRCS Web Soil Survey was used to develop graphic summaries of changes in peak standing herbage along west-east transects through Texas, Colorado-Kansas, and Wyoming-South Dakota. The amount of herbage produced per inch of precipitation increases as average annual precipitation increases on all 3 transects.

Eastward increases in yield response also correspond to lower elevations, longer growing seasons, and higher soil fertility. On rangeland in high ecological condition, about twice as much herbage is produced per inch of rain when annual precipitation doubles in the southern and central Great Plains.

Average yield per inch of annual precipitation increases from about 74 to 144 lb/in through Texas, from about 58 to 153 lb/in from eastern Colorado through Kansas, and from 85 to 124 lb/in from eastern Wyoming through South Dakota.

South Dakota

Herbage production per inch of precipitation on loam soils near Bill WY, Edgemont SD, White River SD, and Winner SD.

Map showing annual yields of 83-120 lbs forage per inch precipitation

Kansas

Herbage production per inch of precipitation on silt loam soils near Bent County CO, Hartland KS, Windhorst KS, Hutchinson KS, and Moran KS.

Map showing annual yields of 51-128 lbs forage per inch precipitation

Texas

Herbage production per inch of precipitation on clay loam soils near Pecos TX, Big Lake TX, San Angelo TX, Goldthwaite TX, and Gatesville TX.

Map showing annual yields of 75-144 lbs forage per inch precipitation