FIRE EFFECTS
SPECIES : Amelanchier alnifolia | Saskatoon Serviceberry 


IMMEDIATE FIRE EFFECT ON PLANT : 
Saskatoon serviceberry is top-killed by moderate to severe fire.  Larger
branches may survive light-severity fire [19,80,95].


DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
NO-ENTRY


PLANT RESPONSE TO FIRE : 
Saskatoon serviceberry sprouts after top-kill by fire [9,19,95].
Bradley [19] found that on burn sites in western Montana, Saskatoon
serviceberry sprouted mostly from upper portions of the root crown.
When the root crown was killed by fire, Saskatoon serviceberry sprouted
from rhizomes further beneath the soil surface.  Seed production may
resume soon after fire:  Saskatoon serviceberry sprouts produced fruits
the second summer after a July 1977 wildfire in Pattee Canyon near
Missoula, Montana [56].

Saskatoon serviceberry cover usually increases [9] or is unaffected
[9,97] by fire.  Even when there is little change between pre- and
postfire cover, fire usually makes Saskatoon serviceberry more
accessible as wildlife browse by lowering shrub height [97].  Arno and
others [9] found that in western Montana, Saskatoon serviceberry cover
generally increased after wildland or prescribed fires in
Douglas-fir/ninebark habitat types.  It sometimes took 10 or more years
before the increase occurred, however.  The authors suggested that slow
recovery in some areas may be due to big game browsing pressure after
fire.

Current-year annual twig production is usually greater after fire in the
absence of heavy browsing pressure [9,24].  In a mountain brush
community in Wyoming, Saskatoon serviceberry mortality was 12 percent,
15 percent, and 15 percent, 1, 2, and 3 years after fall wildfire,
respectively.  Mortality after spring prescribed burning a nearby site
was one, two, and two percent at postfire years 1, 2, and 3.  Postfire
browsing pressure was not heavy, but wildfire- and prescription-burned
areas were browsed more than unburned areas.  Despite this, current-year
twig production was significantly greater on burned sites than on
unburned sites in postfire years 1 to 3.  Current-year annual twig
production was greater on the wildfire-burned site than on the spring
prescribed-burned site (37 vs.  15 g/plant) [24].

Fire season:  In a western Montana study contrasting the ability of
spring vs. fall prescribed fire to improve wildlife habitat, severe fall
fire killed 15 percent of Saskatoon serviceberry plants on the site,
while a less severe spring treatment killed only 5 percent.  Sprouting
response in the first 2 postfire years was greater on the spring burn
[79].

Fire in various habitat/plant community types:  In a western redcedar
(Thuja plicata)/ninebark habitat type of central Idaho, Saskatoon
serviceberry sprouted from the root crown and grew rapidly after
prescribed burning.  Height growth of sprouts follows [11].  (Prefire
height not available.)
                             Height (m)
                    __________________________
                    Avery Site     Lochsa Site
postfire year 1         0.9            1.2
postfire year 2         1.5            1.3
postfire year 3         1.2            3.0
unburned control        2.3            3.2 

In Douglas-fir/blue huckleberry (Vaccinium membranaceum) habitat types
of western Montana, prescribed fire had little effect on Saskatoon
serviceberry cover [11].

Near Ketchum, Idaho, a prescribed fire was conducted on August 1, 1963,
to reduce dwarf-mistletoe (Arceuthobium douglasii) infestation in
Douglas-fir and to promote sprouting of browse, which was above
browseline.  The fire was successful in both respects.  Saskatoon
serviceberry recovered from the fire as follows [68,69]:

            Plants*/1,000 sq ft      Percent Canopy Cover
            ___________________      ____________________
prefire            0.2                       0.25 
postfire yr 1      0.1                       0.03
postfire yr 2      0.1                       0.05
postfire yr 3      0.2                       0.06
postfire yr 4      0.1                       0.06
postfire yr 5      0.1                       0.09
postfire yr 6      0.3                       0.12
postfire yr 7      0.2                       0.12
___________________________________________________________________________
*only plants over 18 inches in height were included in density measurements

After prescribed fire in Oregon white oak (Quercus garryana) woodlands
in western Washington, Saskatoon serviceberry sprouts were most common
on sites that were treated with low-severity fire and had no prefire
mechanical disturbance.  Saskatoon serviceberry sprouts usually
co-occurred with Oregon white oak sprouts on such sites.  Neither
Saskatoon serviceberry sprouts, Saskatoon serviceberry seedlings, nor
Oregon white oak sprouts occurred on microsites that were heavily
disturbed before fire.  After prescribed fire, those microsites were
colonized by herbs, especially exotic herbs, and Oregon white oak
seedlings [1].

Saskatoon serviceberry appears to be slow to recover from prescribed
burning in the sub-boreal spruce-fir (Picea-Abies spp.) zone in British
Columbia [45]. 

Response to very frequent fire:  Saskatoon serviceberry response to
repeated burning is unclear.  In a quaking aspen-rough fescue (Festuca
scabrella) ecotone in Alberta, Saskatoon serviceberry was one of the few
woody shrubs that was not harmed by low-severity annual spring
prescribed fire.  Frequency was 8 percent on unburned sites and 16
percent on annually burned sites.  Canopy cover was not significantly
different between the two areas (4 and 1.4 percent, respectively) [5].

In the Willamette Valley of Oregon, Kalapuyan Indians apparently
controlled Saskatoon serviceberry with frequent fire in order to promote
acorn production by Oregon white oak.  Open oak savannas were noted by
early travellers, but in the absence of aboriginal burning, Saskatoon
serviceberry has formed a closed subcanopy in Oregon white oak woodlands
[18].


DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
NO-ENTRY


FIRE MANAGEMENT CONSIDERATIONS : 
Saskatoon serviceberry is most vigorous in seral plant communities
[9,48,51], and prescribed fire can be used to maintain and/or promote
seral communities.  On big game rangelands, prescribed fire can improve
condition of Saskatoon serviceberry and other shrubs by reducing shrub
height, promoting growth of new twigs, and increasing nutritional
content of browse [9,68,73].  Sites where prescribed burning may harm
Saskatoon serviceberry in the long term include harsh (especially very
dry) sites with low Saskatoon serviceberry density [48], and very cold
sites where postfire growth would be limited by temperature [45].

Fire stimulates production of Saskatoon serviceberry by killing
understory conifers, removing old Saskatoon serviceberry topgrowth, and
promoting sprouting [9,73].  On Douglas-fir/ninebark winter elk range on
the Lolo National Forest, Montana, Makela [71] found that after spring
prescribed fire, biomass production of new Saskatoon serviceberry twigs
was significantly greater (p < 0.1) on burned sites than on unburned
sites the first two growing seasons after fire.
        
Ponderosa pine:  Saskatoon serviceberry usually occurs in the moister,
cooler ponderosa pine habitat types.  Average loading of downed and dead
woody fuels is slightly higher than in drier ponderosa pine types.  Fire
hazard is further increased by the tendency of this type to form
subcanopies and dog-hair thickets of conifer saplings.  Wildfire hazard
is particularly high in this type during drought.  Common management
objectives are to eliminate large areas of overstocking and create a
two-storied stand rather than a multilayered one.  Periodic prescribed
surface fire in early spring or late fall is recommended.  Fuels
management includes treatment of slash following logging and thinning,
and controlling stocking levels.  Scattered thickets of Saskatoon
serviceberry and other shrubs can be left for wildlife [34].

Quaking aspen:  Light fuels and grazing can inhibit fire spread in
quaking aspen.  Brown and Simmerman [22] assigned probabilities of
successful prescribed burning in quaking aspen/Saskatoon serviceberry
habitat types as follows:

                                            Fuel Type
                        _____________________________________________________
       
Grazing    Woody Fuel   Aspen/serviceberry   Mixed aspen-conifer/serviceberry
_____________________________________________________________________________
ungrazed     light            high                       high
ungrazed     heavy            high                       high
grazed       light            moderate                   moderate
grazed       heavy            high                       high

Related categories for SPECIES : Amelanchier alnifolia | Saskatoon Serviceberry