Drought Tolerance in Two Perennial Bunchgrasses Used for
Restoration in the Intermountain West, USA An ideal restoration
species for the semi-arid Intermountain West, USA would be one
that grows rapidly when resources are abundant in the spring,
yet tolerates summer’s drought. We compared two perennial C3,
Triticeae Intermountain-native bunchgrasses, the widely
occurring Pseudoroegneria spicata and the much less widespread
Elymus wawawaiensis, commonly used as a restoration surrogate
for P. spicata. Specifically, we evaluated seedlings of multiple
populations of each species for biomass production, water use,
and morphological and physiological traits that might relate to
drought tolerance under three watering frequencies (WFs) in a
greenhouse. Shoot biomass of E. wawawaiensis exceeded that of P.
spicata regardless of WF. At low WF, E. wawawaiensis displayed
38% greater shoot biomass, 80% greater specific leaf area (SLA),
and 32% greater precipitation use efficiency (PUE). One E.
wawawaiensis population, E-46