Soil climate and plant community relationships on some rangelands of northeastern Nevada

Abstract

Soil temperature and moisture data were collected between 1983 and 1986 on 1 forest and 11 sagebrush-dominated rangeland plant community types of the Humboldt National Forest in northeastern Nevada. Six soil parameters were used to contrast differences between the community types studied: mean annual soil temperature, mean summer soil temperature, starting date (i.e., when soil temperature at 0.5 m exceeded 5 degrees C), growing period (i.e., number of days when soil temperature and moisture were not limiting to growth), soil degree days (i.e., number of days that soil temperature at 0.5 m exceeded 5 degrees C), and growing period percentage (i.e., growing period/soil degree days). These soil parameters were effective in discriminating between most plant community types, yet their effectiveness varied considerably among types. Certain community types (e.g., mountain sagebrush [Artemisia tridentata Nutt. subspecies vaseyana]-bluebunch wheatgrass [Agropyron spicatum Pursh.]) occupy a wide range in soil temperature and moisture, which limits their indicator significance for predicting soil climate. Short growing periods of 25 to 150 days, characterize the rangeland plant community types studied. The onset of the growing period (starting date) occurs between 6 March and 1 July. Such information facilitates the determination of range readiness by plant community type in the study area.