More info for the terms: cover, fire severity, prescribed burn, prescribed fire, root crown, severity
Bitter cherry sprouts from the root crown following fire [47,105].
Since root sprouting has been documented in bitter cherry [28] it
probably also sprouts from roots after fire. It establishes from buried
seed or seed dispersed onto burned sites [114]. Several studies have
reported rapid recovery and substantial postfire increases in bitter
cherry densities [16,33,112]. In an Oregon coastal brushfield, bitter
cherry sprouted from roots 4 months after fire [138]. In an Oregon red
alder (Alnus rubra)-dominated brushfield burned on August 9, 1974, bitter
cherry started sprouting within 2 to 3 weeks. By November, bitter
cherry was sprouting vigorously and stems were 3.3 feet (1 m) tall
[106].
In Montana a prescribed fire occurred on April 13, 1988. Plots were
observed from mid-July to mid-September. Bitter cherry sprout twig
weights on burned plots exceeded twig weights on unburned plots by a
factor of 4 on southwest-facing forested types and by a factor of 9 on a
southeast-facing forested type [76].
In northern Idaho more bitter cherry sprouts are produced per surviving
plant after spring fires than fall fires; however, sprout height is
usually greater after fall fires. Bitter cherry recovery trends 1 year
after a prescribed fire in seral brushfields in northern Idaho are
presented below [73]:
time of fire
spring fall
average # of basal sprouts per plant
prefire 0.4 0.5
postfire 18.3 15.2
average height basal sprouts (ft)
postfire 2.0 2.6
average crown diameter (ft)
prefire 5.0 4.7
postfire 1.9 2.3
average crown height (ft)
prefire 15.1 13.9
postfire 3.4 4.1
A seral brushfield in northern Idaho was prescribed burned in 1965,
1970, and 1975. Bitter cherry sprouted from the root crown and a few
seedlings were observed. The average prefire crown height and diameter
were 8.4 feet and 1.6 feet, respectively. Bitter cherry recovery trends
2 years after the prescribed fires are presented below [70]:
year
1966 1971 1976
maximum crown height (ft) 5.2 5.5 4.1
maximum crown diameter (ft) 2.2 2.5 2.0
Idaho studies investigating postfire successional patterns in a western
redcedar (Thuja plicata)/queencup beadlily (Clintonia uniflora) habitat
type found that bitter cherry regenerated predominantly from seedbanks.
Seedling establishment was affected by fire severity. Bitter cherry
seedlings had greatest percent cover on low-severity burns in postfire
years 1 to 3; in postfire years 4 and 5, bitter cherry seedling percent
cover was greatest on high-severity burns [87,89].
A seral brushfield in northern Idaho was prescribed burned on May 2,
1966; all aboveground vegetation was "totally consumed". In May 1967,
257 bitter cherry seedlings were observed. By May 1968, 14 bitter
cherry seedlings remained [69]. In northeastern Idaho, on a May 14,
1975 prescribed burn, seven bitter cherry seedlings were observed in
postfire year 2. By postfire year 4, four seedlings remained [71]. In
Oregon a Douglas-fir (Pseudotsuga menziesii) clearcut was prescribed
burned in late fall. Bitter cherry seedlings were present postfire year
1 on the burned site but were not present in adjacent virgin forest
[33].
In Oregon 240 acres (96 ha) of a Douglas-fir watershed was harvested
over a 4-year period from the fall of 1962 to the summer of 1966. It
was broadcast burned in October 1966. Bitter cherry reached peak
abundance about 10 years after fire [39]. In north-central Idaho in a
grand fir (Abies grandis)/pachistima habitat type, 36 stands
representing 1, 3, 8, 12, and 23 year age classes and 7 near-climax
stands were clearcut and broadcast burned. Canopy cover and height of
bitter cherry for each age class were as follows [136]:
canopy cover height
(%) inches centimeters
age class
1 0.1 9 22
3 0.1 17 44
8 0.4 25 63
12 0.9 49 122
23 0.3 38 95
near-climax 0.0 -- --
In the western Cascades bitter cherry was absent from undisturbed
old-growth Douglas-fir stands, but was abundant on Douglas-fir
plantations that were clearcut and broadcast burned 2 to 40 years ago.
Shrub dominance decreases at 20 to 30 years with canopy closure [108].