Degree of Threat: Unknown
Comments: Sagebrush is not fire-tolerant and relies on wind-blown seeds from outside the burned area for re-establishment. Big sagebrush is readily killed when aboveground plant parts are charred by fire. If sagebrush foliage is exposed to temperatures above 195 degrees Fahrenheit (90C) for longer than 30 seconds, the plant dies. Among the three major subspecies of big sagebrush, basin big sagebrush is considered intermediate in flammability. Mountain big sagebrush is most flammable, and Wyoming big sagebrush is least flammable. Since the advent of effective fire control and intensive livestock grazing (reducing ground fuel and understory competition), regeneration and establishment of western juniper have expanded into suitable sites previously dominated by Artemisia tridentata. Western juniper (Juniperus occidentalis) is also intolerant of fire and historically, spread was restricted by natural fires (Tirmenstein, 1999). This expansion of young stands of western juniper is common in Oregon, Idaho, and northeastern California (Burns and Honkala, 1990). However, suppression of fire results in hotter and longer burning fires that are typically followed by the spread of the invasive cheat grass (Bromus tectorum). Especially in Washington state, habitat loss and fragmentation pose the greatest threat to the species (Gamon, pers. comm., September 2011).