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Wildlife, Animals, and Plants
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FIRE EFFECTS
SPECIES: Pinus coulteri | Coulter Pine
IMMEDIATE FIRE EFFECT ON PLANT :
Large Coulter pine are resistant to all but severe surface fires.
Younger trees are apparently killed by moderate-severity surface or
crown fires [23,54]. No data are available concerning the effect of
crown fire on large-diameter Coulter pine.
A "hot" surface fire on Mt. Diablo killed nearly all Coulter pine,
including large trees. In an area of the mountain where fire was less
severe, however, 9 of 52 Coulter pine survived. Of these trees, all of
those greater than 16 inches (40 cm) in d.b.h. survived, and only one
tree less than 16 inches in d.b.h. survived. Surviving trees had needle
scorch only on lower branches [54].
DISCUSSION AND QUALIFICATION OF FIRE EFFECT :
NO-ENTRY
PLANT RESPONSE TO FIRE :
Coulter pine readily establishes from seed on burned sites [52].
Persisting cones on surviving trees, and sometimes on those killed by
fire, provide a source of seed [38,52]. Seedling establishment is
usually greatest during the first postfire year [7]. The severe Marble
Cone Fire in the Santa Lucia Mountains destroyed Coulter pine stands.
At postfire year 1, a large number of Coulter pine seeds germinated.
Three seasons following the fire, Coulter pine seedling density ranged
from 18 to 4,213 per acre (7-1,685/ha). The lower seedling densities
probably resulted from interference by annual ryegrass [19].
Vale [54] found that pine seedling density was much greater after the
Mt. Diablo fire than before it (newly-germinated pines could not be
identified by species). Pine seedling numbers were greatest in areas
where fire was less intense. In these areas, relative frequency of pine
seedlings was 100 percent; density was 2 seedlings per square meter. In
areas where fire was severe, relative frequency was only 56 percent, and
density was one seedling per square meter. Vale suggested that the
intense heat in the heavily burned areas may have destroyed seeds within
the cones of trees, but the less intense heat in the more lightly burned
areas may have opened cones without destroying seeds. Pine seedlings
were disproportionately located on areas where mineral soil was exposed.
DISCUSSION AND QUALIFICATION OF PLANT RESPONSE :
NO-ENTRY
FIRE MANAGEMENT CONSIDERATIONS :
Intense fire may be responsible for reducing the distribution of Coulter
pine [52,57]. Fire intensity in chaparral, woodland, and forest
vegetation is probably greater since inititation of fire suppression
[56], and intense fire reduces Coulter pine populations. Frequent,
moderate-severity surface fires, however, would probably benefit this
species. The differential survival of large trees in less intensely
burned areas and enhanced reproduction on exposed mineral soil in such
areas both suggest that most Coulter pine evolved under a regime of
frequent, light- to moderate-severity surface fires [54]. Managers
should keep in mind, however, that Coulter pine in Coulter pine-coast
live oak communities may be harmed by fire [7].
Prescribed burning has been used in Coulter pine/manzanita stands to
reduce fuel loading [11,51]. Severe fires or fires at too-frequent
intervals, however, convert such communities to mixed stands of
manzanita and ceanothus [52,55].
Frequent fire selects for Coulter pine over bigcone Douglas-fir in
canyon live oak (Quercus chrysolepis) communities [38].
Under long fire return intervals, Coulter pine invades oak savanna
[17,22,45].
Related categories for Species: Pinus coulteri
| Coulter Pine
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