• FIRE ECOLOGY OR ADAPTATIONS
• POSTFIRE REGENERATION STRATEGY

FIRE ECOLOGY OR ADAPTATIONS:

Young western junipers have thin bark and are readily killed by surface fires. "Older" trees with thicker bark are described as "moderately resistant" to fire [87]. In general, the taller the juniper, the greater the severity of the fire required to kill it [64]. Western juniper does not sprout [19]. Reestablishment is through seed that is dispersed fairly slowly by water and animals.

Fire regimes in western juniper communities: When fires occurred at 10 to 25 year intervals, western juniper was restricted to protected microsites [1]. Belsky [8] reports that "at current levels of livestock grazing and fire control, western juniper woodlands represent the final phase of vegetative succession in parts of Oregon, California, and Idaho." In climax western juniper communities, all age classes are typically represented from seedlings to trees several hundred years in age [96].

Fire return intervals in western juniper communities range from 7 to 25 years to more than 100 years [2]. Mean fire interval for western juniper within the Columbia River Basin is estimated at 52 years [6]. Fire return intervals within western juniper communities have been reported as follows:

California:   7-17 years
southwestern Idaho:   25 years
Nevada:   15-20 years [1]
southwestern Oregon:   < 20 years [19]

In western juniper woodlands of the San Bernardino Mountains of California, infrequent canopy fires produce a mosaic of fairly small scattered patches within uniform stands [99].

Fire regimes in other communities: The range of fire intervals reported for some species that dominate communities where western juniper occurs are listed below. To learn more about the fire regimes in those communities refer to the FEIS summary for that species, under "Fire Ecology or Adaptations."

Pacific ponderosa pine (Pinus ponderosa var. ponderosa):  2-42 years
red fir (Abies magnifica var. magnifica):  10-65 years
          (Abies magnifica var. shastensis):  70-130 years

POSTFIRE REGENERATION STRATEGY:

Tree without adventitious bud/root crown
Initial off-site colonizer (off-site, initial community)
Secondary colonizer - off-site seed

Related categories for SPECIES: Juniperus occidentalis | Western Juniper