Root distribution and soil water regimes in nine habitat types of the northern Rocky Mountains

Abstract

Root distribution and the annual cycle of' soil water availability were measured in nine habitat types of the northern Rocky Mountains. Water stress periods became progressively longer under Abies lasiooarpa forests, Populus trerrruloides groves, Pseudotsuga menziesii forests, Festuoa idahoensis grasslands, Artemisia tridentata shrublands, and Agropyron spioatum grasslands. Water stress periods were longer under Pseudotsuga forests than under adjacent logged areas. Live feeder root biomass (1) was similar under grassland, shrubland, and forest types, (2) increased within a vegetation type with altitude, and (3) decreased at a site with depth. Seral grasslands had less live feeder root biomass than forests in the same habitat type, but climax grasslands and forests were similar in root biomass.