More info for the terms:
adventitious,
lignotuber,
litter,
mesic,
natural,
seed,
shrubsHollyleaf cherry can regenerate sexually or vegetatively. It is a
widespread component of fire-prone environments and maintains itself
primarily through vigorous sprouting. Little or no seedling
establishment occurs immediately following fire [
24,
43]. Extended
fire-free periods create conditions favorable to seedling establishment
and population expansion [
25,
26].
Seed regeneration: Hollyleaf cherry starts producing seed as early as 3
years of age [
14]. As with most chaparral shrubs, seed is produced
almost annually after the first flowering [
38], and production does not
appear to decrease with age [
22]. Seeds are dispersed in the fall [
25].
Large numbers of the fleshy, one-seeded fruits fall directly beneath the
parent plant, but widespread dispersal also occurs through animal
vectors, particularly birds [
14,
23,
40,
49]. The seeds are short-lived.
Viability is retained no longer than 9 months when seed is allowed to
dry at room temperatures [
25]. Seeds germinate readily under suitable
moisture and temperature conditions; they do not require the stimulus of
heat or charred wood for germination [
25,
38,
50]. Germinative capacity
of stored seeds was 24 percent when stratified for 90 days in a moist
medium at temperatures ranging from 33 to 41 degrees F (0.6 to 5 degrees
C) [
14]. Germination is apparently inhibited by constant darkness [
25].
In the nursery, seedling emergence occurred within 20 to 40 days after
sowing [
8]. Natural germination apparently takes place during the
winter or spring immediately following dispersal [
38].
Unlike many chaparral species, hollyleaf cherry is not dependent on
fire-created gaps for establishment [
23,
43]. Instead, hollyleaf cherry
is able to establish seedlings during fire-free periods, utilizing gaps
created by the death of shorter-lived species [
44]. Limited hollyleaf
seedling establishment has been observed in a 25-year-old stand of
chamise chaparral in openings previously occupied by hoaryleaf ceanothus
(Ceanothus crassifolius) [
20]. Increased seedling establishment is
generally restricted to more mature chaparral stands, usually those
ranging from 60 to 100+ years of age [
26,
36]. Germination and seedling
growth are apparently favored on mesic sites (north slopes) which
possess a well-developed litter layer [
26,
36]; litter layers beneath
mature stands of scrub oak chaparral may reach up to 8 inches (20 cm) in
depth [
17]. Seasons of above-normal precipitation may also be important
for hollyleaf cherry seedling establishment [
24,
43]. Although seedlings
may initially establish beneath mature chaparral, seedling recruitment
into the population is never very abundant [
23,
26]; seedlings are
frequently stunted and are susceptible to browsing by small mammals
[
36,
45,
46]. For chaparral species capable of establishing between
periodic fires, Zedler [
44] suggests that gap size may be crucial to a
seedling's ability to survive to the stage where it can sprout
following fire. Suitable gaps for the successful establishment of
hollyleaf cherry are apparently more prevalent in older stands of
chaparral. On favorable growth sites in a 65-year-old stand of scrub
oak chaparral, hollyleaf cherry seedlings reached heights of 28 inches
(70 cm) within 6 years [
36].
Vegetative regeneration: In the absence of fire, many long-lived
sprouters within stands of mature chaparral rejuvenate their canopy by
continually producing new sprouts from established rootcrowns [
24,
26].
Generalized information on obligate sprouting species within chaparral
suggests that hollyleaf cherry also maintains itself in this manner
[
24]. Following disturbances such as fire or cutting, hollyleaf cherry
also regenerates vegetatively from adventitious buds located on stumps
or root crowns [
5,
40]. This species apparently does not develop an
ontogenetically derived lignotuber [
23,
24].