FIRE EFFECTS
SPECIES: Washingtonia filifera | California Palm 



IMMEDIATE FIRE EFFECT ON PLANT : 
The immediate effect of fire on an individual California palm varies
according to the tree's fire history.  Fire causes the greatest
reduction of outer vascular bundles with the initial burning of the
highly flammable shag [40].  Typically, all dead leaves are burned as
well as most of the living rosette of leaves [32].  The trunk may be
repeatedly burned as leaves in the crown detach and slide down the
trunk, ringing the base with fresh fuel.  Subsequent fires burn lesser
amounts of the trunk because the shag, previously removed by fire,
requires a number of years to regain thickness and length.  Each
subsequent fire further chars the trunk surface, increasing fire
resistance [40].  No data are available on the effects of fire on
seedlings.  Vogl [40] believes seedlings require a fire-free period of a
few years before fire resistance is attained.


DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
NO-ENTRY


PLANT RESPONSE TO FIRE : 
Fire releases saplings suppressed by the shade of shrubs.  Young
palms, freed from competition for water and sunlight, grow vigorously
in fire-opened sites [40].

Flower and fruit production nearly doubles in crown-scorched trees
during the first postfire growing season [8,32].


DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
NO-ENTRY


FIRE MANAGEMENT CONSIDERATIONS : 
Fire is an essential element of California palm regneration and oasis
maintenence.  Fire suppression, practiced in many oases for over 60
years, has resulted in dense understories of brush and young palms.  The
Thousand Palms Oasis, for example, located in the Colorado Desert,
California, developed very little understory for 10 to 15 years
following its last fire.  Saltgrass was the understory pioneer.  It was
displaced by a dense growth of mesquite (Prosopis juliflora; P.
pubescens) and goldenbush.  After 35 years of fire suppression the oasis
supported a dense, tall undergrowth with a humid microclimate.  Litter
accumulations were "massive" [40].  California palm's ability to resist
fire under such highly flammable conditions is unknown.  Managers are
concerned that current fuel loading in many oases constitutes a severe
fire hazard to palms, and that the next fire will kill substantial
numbers of mature trees [1,40].  Manually removing portions of the
understory, followed by natural prescribed and/or prescribed fire is
recommended [1].

Fire kills desert palm borer beetle larvae near the trunk exterior
[8]. 

Related categories for Species: Washingtonia filifera | California Palm