FIRE EFFECTS
SPECIES: Pinus jeffreyi | Jeffrey Pine 



IMMEDIATE FIRE EFFECT ON PLANT : 
Jeffrey pine has adapted to withstand low-severity fires in wellspaced
stands.  Moderate- to high-severity fires will, however, kill trees pole
size and smaller.  Mature Jeffrey pines can survive most fires,
suffering only bole scorch.  These fire effects are intensified with
tree density and fuel load.  Depending on the season, Jeffrey pine may
experience extensive heat-kill of foliage, but may receive only light
damage to buds and twigs.  Wagener [43,44] found that bud kill is more
important than foliage kill in determining survival of Jeffrey pine.
More than 50 percent of live buds are usually needed for a tree to
survive.  High-severity fires may also scorch bark and kill cambium
[44].

Fire-damaged Jeffrey pines are weakened physiologically, and for 2 or
more years are more susceptible to insect attacks than are undamaged
trees [44].  Insects have been found to reproduce and deposite eggs in
the scorched bark of Jeffrey pine within 24 hours after ignition.  Adult
pine beetles (Arhopalns asperatus) were found on the basal 3 feet (1 m)
of the most severely scorched tree [45].


DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
NO-ENTRY


PLANT RESPONSE TO FIRE : 
Jeffrey pine response to fire will vary according to fire severity, age,
and season.  High-severity fires that occur during periods of high
stress will generally result in death.  Low- to moderate-severity fires
will generally restrict the growth and regeneration of the tree, but
recovery is usually evident the following year [26].  Jeffrey pine has a
weak tendancy to put out vigorous epicormic shoots bearing juvenile
foliage on stem and branches [34].  Standing fire-killed Jeffrey pine
trees will not deteriorate appreciably until the third year after fire
[23,43].


DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
NO-ENTRY


FIRE MANAGEMENT CONSIDERATIONS : 
Primary fire management considerations involve postfire activities.
Jeffrey pine is very susceptible to insect damage, and the success of
silvicultural regeneration depends upon the proper management decisions.
Whenever possible, areas of complete kill should be logged first in
order to hinder subsequent insect attacks.  Smaller diameter trees are
more likely to be infested than larger ones.  Therefore, initial logging
should concentrate on smaller timber, thus maximizing the potential
salvage volume [43].  Expedient marking of live and dead Jeffrey pine
trees is necessary in order to better manage the stand for commercial
and silvicultural treatments [44].

Related categories for Species: Pinus jeffreyi | Jeffrey Pine