FIRE EFFECTS
SPECIES: Mahonia repens | Oregon-Grape 



IMMEDIATE FIRE EFFECT ON PLANT : 
Oregon-grape usually survives all but severe fires that remove duff and
cause extended heating of the upper soil [17,48].  One study reported
that a severe fire favored Oregon-grape [11], but fire conditions were
not specified.


DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
NO-ENTRY


PLANT RESPONSE TO FIRE : 
Oregon-grape was absent after severe fires in northern Idaho but
unharmed by moderate fires [6].  Density and height increases have been
noted in the second postfire growing season [48].



DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
Five years following a moderate- to high-intensity fire, Oregon-grape
reached 60 percent of prefire biomass in a mixed aspen/conifer stand, 65
percent in an upper elevation aspen stand, and 85 percent in a lower
elevation aspen stand [12].

Four different fires were studied to determine successional responses of
Oregon-grape following fire.  At postfire year 1 cover had decreased,
remained the same at postfire year 2, decreased in postfire year 9, and
was much higher at postfire year 18.  Fire severity may be related to
the survival of Oregon-grape.  Generally, an increase in cover should
occur by 9 postfire years [44].

Oregon-grape cover increased during postfire years 1 and 2 following an
April fire in western Montana.  It invaded an burn resulting from an
October fire during the second postfire year [48].


FIRE MANAGEMENT CONSIDERATIONS : 
Oregon-grape may be supressed in areas seeded to grass following
wildfires.  This should be considered before planting grasses in areas
where Oregon-grape is an important food for wildlife [5].  Prescribed
fire has a low probability of success in the aspen/low forb community
type, of which Oregon-grape is a main component, because of the sparse
vegetation [13].

Related categories for Species: Mahonia repens | Oregon-Grape