FIRE EFFECTS
SPECIES: Iliamna rivularis | Wild Hollyhock 



IMMEDIATE FIRE EFFECT ON PLANT : 
NO-ENTRY


DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
NO-ENTRY


PLANT RESPONSE TO FIRE : 
Wild hollyhock is a residual colonizer that is prominent in initial
postfire communities, even after holocaustic fires [26].  It becomes
abundant following severe wildfire and hot broadcast burning,
particularly when slash has been piled [22].

Wild hollyhock dominated the postfire vegetation after moderate to
severe fire in quaking aspen and quaking aspen-mixed conifer habitats in
Idaho.  It formed dense stands within the first postfire growing season,
but was absent from the preburn vegetation.  It continued to dominate
the site for several seasons, producing an average of 2,000 pounds per
acre (2,260 kg/ha) in postfire year 2, and 835 pounds per acre (940
kg/ha) in postfire year 3.  By postfire year 4, production had further
declined, and wild hollyhock foliage appeared chlorotic.  It disappeared
from the site by the sixth growing season following the fire.  In
postfire year 2, wild hollyhock produced an average of 1,329 seeds per
square foot (14,300 seeds/sq m) [3].

In Douglas-fir habitats in central Idaho, wild hollyhock was prominent
in postfire communities but was absent from preburn vegetation.  It had
the following frequencies in postfire growing seasons:  year 1, 52
percent; year 2, 36 percent; year 3, 52 percent; year 4, 52 percent;
year 5, 56 percent; year 6, 52 percent; and year 7, 48 percent.  Wild
hollyhock had a frequency of 4 percent in an adjacent 20-year-old burn.
By postfire year 3, it dominated the site along with fireweed (Epilobium
angustifolium).  Together, they comprised 40 percent of total vegetal
cover.  In successive years, they made up 20 percent of total cover, but
were not as abundant after postfire year 6 [18].

In general, wild hollyhock flowers profusely and becomes very abundant
for a short period following fire but is eventually replaced by other
vegetation [13,24,28].  It has shown this response after fires in grand
fir [31], ponderosa pine (Pinus ponderosa) [21], aspen (Populus spp.)
[4], and Douglas-fir [1,5] habitats in the Northwest.


DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
NO-ENTRY


FIRE MANAGEMENT CONSIDERATIONS : 
NO-ENTRY

Related categories for Species: Iliamna rivularis | Wild Hollyhock