FIRE ECOLOGY
SPECIES: Adenostoma fasciculatum | Chamise 



FIRE ECOLOGY OR ADAPTATIONS : 
Following fire, chamise sprouts from dormant buds on the lignotuber
[60,68,73].  The lignotuber has a stored supply of carbohydrates,
nutrients, and water which support vigorous growth [60].  Chamise also
produces abundant seedlings from fire-activated, soil-stored seed
[16,68].  Chamise rapidly reoccupies the postfire community.

Chamise possesses a number of adaptations that enhance its flammability
[39,93,104,116].  These adaptations result in intense, fast-spreading,
potentially large fires which have an increased probability of occurring
as a stand matures [104].  Chamise chaparral produces fuel loadings
capable of supporting a moderately intense fire within approximately 15
years [103].  Adaptations which enhance flammability are discussed below.

     Chemical:  The chemical composition of foliage includes high energy
     ether extractives (waxes, resins, oils, terpenes, and fats) and
     inorganic minerals that affect pyrolysis of carbohydrates [111].
     Ether extractives in the foliage increase burning rate because of
     their high heat content and may account for as much as 34 percent
     of the available heat content of chamise [104].  In older plants, a
     significant increase in the ether extractive content of 1- and
     2-year-old leaf and stem tissues apparently contributes to the
     increased flammability of older stands [116].  Volatile, high
     energy essential oils on the leaf surface also ignite at low
     temperatures [115,116].

     Physical:  Structural characteristics produce rapid rates of
     energy release [21,116].  Approximately 60 percent of chamise stems
     are less than 0.5 inches (1.27 cm) in diameter [21].  Large amounts
     of small-stemmed material, distributed continuously from ground
     level throughout the multistemmed canopy, lend spatial continuity
     to the fuelbed and facilitate heat transfer [104].  Chamise also
     retains dead material in the crown [116].  As a stand ages, this
     material accumulates and within 30 years may account for 50 percent
     of the fuel loading [111].  Besides igniting easily and burning
     fast, dead fuels preheat live fuels, further increasing stand
     flammability [21,111].

     Physiological:  Chamise is most flammable in the fall [111].  Fuel
     moisture drops significantly during hot, dry weather and increases
     the concentration of extractive chemicals [115].


POSTFIRE REGENERATION STRATEGY : 
   Tall shrub, adventitious-bud root crown
   Small shrub, adventitious-bud root crown
   Ground residual colonizer (on-site, initial community)

Related categories for Species: Adenostoma fasciculatum | Chamise