FIRE CASE STUDIES
SPECIES: Vaccinium myrtillus | Dwarf Bilberry 



CASE NAME : 
Table Mountain burn, eastern Washington


REFERENCE : 
Woodard, P. M. 1977 [111]


SEASON/SEVERITY CLASSIFICATION : 
September 30, 1975  - severity not reported.


STUDY LOCATION : 
The study site is located in Kittitas County, Washington on the east
side of the Cascades, approximately midway between Ellensburg and
Wenatchee.


PREFIRE VEGETATIVE COMMUNITY : 
Two areas, both of which occur in the subalpine fir zone, were included
in the study.  Both sites were representative of the Engelmann spruce
(Picea engelmannii)-subalpine fir (Abies lasiocarpa)-elk sedge (Carex
geyerii) habitat type as delineated by Wirsing (1973).  The lodgepole
pine thicket site was described as a "well-developed,
well-differentiated" stand.  All layers of the overstory were well
stocked with lodgepole pine, the dominant overstory species.  Subalpine
fir and Engelmann spruce codominated the intermediate crown class.
Common understory dominants included elk sedge (Carex geyerii),
heartleaf arnica (Arnica cordifolia), broadleaf arnica (Arnica
latifolia), Hood sedge (Carex hoodii), bigleaf lupine (Lupinus
polyphyllus), and dwarf bilberry (Vaccinium myrtillus).

The snag site consisted of decadent lodgepole.  Many snags were present
in the overstory with living lodgepole pine, subalpine fir, and
Engelmann spruce.  Subalpine fir and Engelmann spruce occurred as
overstory codominants although only subalpine fir was regenerating
beneath the closed canopy.  Subalpine fir, elk sedge, broadleaf arnica
(Arnica latifolia), pinegrass (Calamagrostis rubescens), and the mosses
Rhacomitrium canescens var. ericoides and Polytrichum commune were
common understory dominants.

Subplots at both sites were thinned to 20 percent of the original crown
cover prior to the burn.


TARGET SPECIES PHENOLOGICAL STATE : 
not reported


SITE DESCRIPTION : 
        elevation - 5,600 to 5,800 feet (1,706-1,761 m)
        slope - 0 to 20 percent
        aspect - south to west, primarily southwest
        topography - much relief
        soils -
                parent material - basalt residuum
                bedrock composition - basalt, andesite, rhyolite
                soil fertility - 
                        lodgepole pine thicket - low
	                snag - moderate
        climate -
                winters - cold and wet
                summers - cool and dry
                annual precipitation - 31.5 to 63 inches (80-160 cm)
                70 percent of annual precipitation occurs as snow
                between October and March


FIRE DESCRIPTION : 
        time of fire - 1400 to 1600 hours
        ambient air temperature - 61 to 63 degrees F (16-17 degrees C)
        relative humidity - 19 to 21 percent
        wind direction - south to southwest, erratic
        wind speed - calm, gusts to 16 miles per hour (26 km/hour)
        days since rain - 15
        fuel moisture (fine) - 13.1 percent
        estimated flame heights - 125 to 140 feet (38-42 m)
        fire description - A back fire was ignited on the north side
                with 9 foot (3 m) strips, then a strip head fire was
                applied to the remainder of area at 49 foot intervals.
                Hand-held drip torches containing a 50/50
                diesel oil-gasoline mixture were used to ignite the
                fire.
        mean duff reductions - 
                        lodgepole pine thicket - from 60 tonnes/ha to
                                4 tonnes/ha
                        snag - from 74 tonnes/ha to 49 tonnes/ha
 


FIRE EFFECTS ON TARGET SPECIES : 
Comparative frequency and cover of dwarf bilberry were documented as
follows:

Lodgepole pine thicket -

                rel. frequency                    rel. cover
        before tmt.   1 yr. after         before tmt.     1 yr. after

burned      .46           .38                 .013            .012
control     .75          1.00                 .078            .070
thinned     .20           .20                 .019            .002

Snag -

                rel. frequency                    rel. cover
        before tmt.   1 yr. after         before tmt.     1 yr. after

burned       .12          .06                  .001           .000
control      .25          .50                  .009           .004
thinned      .20          .20                  .001           .013

Dwarf bilberry regenerated from rhizomes after fire, but in general,
postfire response was poor.


FIRE MANAGEMENT IMPLICATIONS : 
Crown fires can kill or drastically reduce sprouters such as dwarf
bilberry.

Related categories for Species: Vaccinium myrtillus | Dwarf Bilberry