FIRE CASE STUDIES
SPECIES: Gaultheria shallon | Salal 




FIRE CASE STUDIES : 
1. Clearcut-burned coastal cedar-hemlock forest, BC
2. Slashburn, eastern Vancouver Island, BC


1st CASE NAME : 
Clearcut-burned coastal cedar-hemlock forest, BC


REFERENCE : 
Lafferty, R. R. 1972 [82]


SEASON/SEVERITY CLASSIFICATION : 
Plot 6 - May 22, 1969/high
Plot 7 - September 9, 1968/moderate


STUDY LOCATION : 
The study site was located approximately 33 miles (53 km) east of
Vancouver and 14 miles (22 km) north of Mission City, British Columbia.


PREFIRE VEGETATIVE COMMUNITY : 
Douglas-fir (Pseudotsuga menziesii) dominated the overstory with
scattered western redcedar (Thuja plicata) and western white pine (Pinus
monticola) on the south and west aspects and western hemlock (Tsuga
heterophylla) and western redcedar on the north and east aspects.  Red
elderberry (Sambucus racemosa), willow (Salix spp.), mountain ash
(Sorbus sitchensis), vine maple (Acer circinatum), red and ovalleaf
huckleberry (Vaccinium parvifolium, V. ovalifolium), trailing blackberry
(Rubus ursinus), thimbleberry (R. parviflorus), salal, fireweed
(Epilobium angustifolium), dwarf Oregon grape (Mahonia nervosa),
northern twinflower (Linnaea borealis), deerfern (Blechnum spicant), and
various mosses were common in the preburn community.


TARGET SPECIES PHENOLOGICAL STATE : 
not reported.


SITE DESCRIPTION : 
Elevation:  500 feet (152 m).
Parent materials:  bedrock was composed of quartz diorite and diorite,
                   overlain with glacial till, outwash and minor
                   lacustrine and aeolian deposits.
Soils:  mixture of colluvium, loess, and ablation till, loamy with mixed
        gravel throughout.  Climate:  marine and cool, no distinct dry
        season.  An average of 203 frost-free days per year.


FIRE DESCRIPTION : 
      rate of           residence         total fuel        energy released
      spread            time              loading           (cal./m sq. x
      (ft./min.)        (min.)            (g/m sq.)         1,000)

Plot 6    22               85             15,840            22,709
Plot 7    15               50             30,308            45,799

      initial duff            residual duff           % duff reduction
      wt. (g/m sq.)           wt. (g/m sq.)           by weight

Plot 6     6,700                  3,750                     44
Plot 7    10,000                  6,710                     33                

      avg. initial      avg. initial      fuel consumed     total energy
      fuel  (g/m sq.    loading (g/m      (g/m sq. x        (cal/m sq. x
      x 1,000)          sq. x 1,000)      1,000)            1,000,000)

Plot 6      8.322          15.022           3.058           22.709 x 10
Plot 7     20.321          30.308           7.946           45.799 x 10

                  percent moisture - slash fuel component
            fine fuel         med. fuel         large fuel
            (.04-2.5 in.)     (.43-3.9 in.)      (4.0 in. or >)
            (.01-1.0 cm)      (.1.1-10 cm)       (10.1 cm or >)    

Plot 6      12.5               6.6                40.3      
Plot 7      17.4              16.3                21.4

                 percent moisture - organic fuel component
            litter            fermentation            humus

Plot 6      21.8                 102.7                120.8
Plot 7      11.8                 146.1                197.8


FIRE EFFECTS ON TARGET SPECIES : 
Plot 6 - high intensity burn:  Very few plants were present after the
burn.  By the third growing season, small colonies of salal were
scattered throughout the plot.

Plot 7 - moderate intensity burn:  Salal was observed the first year
after fire.  Salal continued to increase in abundance during the first
three growing seasons after fire.  Recovery was as follows:

                   1969        1970        1971
                 postburn

% freq.            51.1       58.0          58.0
% cover             1.1        2.9          5.6


FIRE MANAGEMENT IMPLICATIONS : 
High intensity burns are more effective in delaying the recovery of
salal than moderate intensity burns.



FIRE CASE STUDIES
SPECIES: Gaultheria shallon | Salal 



2nd CASE NAME : 
Slashburn, eastern Vancouver Island, BC


REFERENCE : 
Vihnanek, R. E.; Ballard, T. M. 1988 [131]


SEASON/SEVERITY CLASSIFICATION : 
not reported/low to high


STUDY LOCATION : 
The study site was located on the east side of Vancouver Island, British
Columbia.


PREFIRE VEGETATIVE COMMUNITY : 
Sites are in the wet and dry, coastal western hemlock (Tsuga
heterophylla) subzone.  The understory was dominated by salal.  Each
site supported planted 5- to 10-year-old Douglas-fir (Pseudotsuga
menziesii), some of which had been burned.


TARGET SPECIES PHENOLOGICAL STATE : 
not reported.


SITE DESCRIPTION : 
Soils:  Brunisols or podzols developed in till, overlying volcanic or
        sedimentary bedrock.  
Slope:  0 to 60 percent.  
Elevation:  1,650 to 2,650 feet (500-800 m).  
Climate:  average annual water deficit - 4.2 to 5.2 inches (106-133 mm).
          mean annual temperature - 41 to 47 degrees F (5.4-8.7 degrees
          C).


FIRE DESCRIPTION : 
Fire severity was estimated on the basis of remaining fuels and percent
exposed mineral soil.  Fire severity ranged from low to high and was defined
as follows:

high - absence of all fine and most medium (3-9.5 cm diameter) fuels,
      considerable consumption of large fuels and stumps and a large
      difference in percent mineral soil exposure between paired burned and
      unburned plots (15-60 percent).

moderate - intermediate fuel characteristics, small to moderate difference in
      paired mineral soil exposure (0-5 percent) between burned and unburned
      plots.

low - fine fuels present (< 2.5 cm in diameter), minimal charring of large
      fuels (> 10 cm diameter) and stumps; small difference (0-4 percent) in
      percent mineral soil exposed on burned and unburned areas.


FIRE EFFECTS ON TARGET SPECIES : 
site burn       salal cover             height              exposed mineral
#    sever-         (%)                 (cm)                soil (%)
     ity*      burned   unburned    burned   unburned      burned  unburned

1    H           16        55         15        28           26       0
2    H           16        54         20        29           15       0
3    M           25        44         18        35            5       1
4    H            4        70         16        49           60       0
5    H            9        44         18        32           31       2
6    H            5        41         18        22           24       0
7    H            9        47         14        28           36       5
8    H            7        55         14        34           25       0
9    L           16        25         28        21            6      10
10   H            6        15         23        24           39      24
11   M           15        40         22        32            4       0
12   M           26        32         25        23            2       4
13   M           41        64         26        36            0       0
14   M           34        52         23        36            6       0
15   L           47        60         31        34            4       0
16   L           15        26         21        21            3       0
17   L           30        63         17        25            6       3
18   L           24        54         16        23            1       1
19   M           19        38         20        25           11       1
20   L           40        51         26        30            1       0

 *L - low severity
  M - moderate severity
  H - high severity


FIRE MANAGEMENT IMPLICATIONS : 
Salal cover and height growth can be significantly reduced by burning
with corresponding increases in the height growth of Douglas-fir
seedlings.  Vihnanek and Ballard [131] note that "results [of this
study] suggest that slashburning should remain as a site preparation
option in the dry salal-dominated forest ecosystems of eastern Vancouver
Island.  However, it would be inappropriate to extrapolate the results
of this study to other kinds of ecosystems."

Related categories for Species: Gaultheria shallon | Salal