FIRE ECOLOGY
SPECIES: Picea engelmannii | Engelmann Spruce 



FIRE ECOLOGY OR ADAPTATIONS : 
Plant adaptations to fire:  Engelmann spruce is very fire sensitive and
is generally killed even by low-intensity fires.  Postfire
reestablishment is via wind-dispersed seeds which readily germinate on
fire-prepared seedbeds.  The occasional mature tree which survives fire,
those escaping fire in small, unburned pockets, and trees adjacent to
burned areas provide seeds to colonize burned sites.  Large trees
occasionally survive light fires [31].

Scattered individuals or pockets of Engelmann spruce trees commonly
escape burning because they occur in wet locations where fire spread is
hampered.  In subalpine habitats, scattered Engelmann spruce trees often
escape fire because of discontinuous fuels, broken and rocky terrain,
and the moist and cool environment [67,88].

Fire regime:  Engelmann spruce-subalpine fir forests usually develop in
cool, moist locations and experience fire-free intervals averaging 150
years or more [8].  Many Engelmann spruce stands are even aged,
suggesting that they developed after fire [54].

Fuels and fire behavior:  The fuel structure in stands dominated by
Engelmann spruce and subalpine fir promotes highly destructive
stand-destroying fires.  Fuel loads are higher than in lower elevation
montane stands, and the fuel beds tend to be irregular and have large
amounts of needle litter accumulating under the narrow crowned trees
[31,91].  The needles are small and fine, and form a compact fuel bed in
which fire spreads slowly [28].  These concentrated, slow-burning fuels
commonly produce flames high enough to reach Engelmann spruce's
low-growing, lichen-draped branches and start crown fires [20,91].


POSTFIRE REGENERATION STRATEGY : 
   crown-stored residual colonizer; short-viability seed in on-site cones
   off-site colonizer; seed carried by wind; postfire years 1 and 2
   secondary colonizer; off-site seed carried to site after year 2

Related categories for Species: Picea engelmannii | Engelmann Spruce