More info for the terms:
cover,
density,
frequency,
hardwood,
natural,
rhizome,
scarification,
seed,
shrubs,
softwoodHighbush cranberry is not considered to be a primary competitor to
conifers but is a component of major brush complexes that occur on
moist, productive sites on floodplains or under deciduous canopies. It
can compete significantly with natural or planted white spruce seedlings
in the Sub-Boreal Spruce and Boreal White and Black Spruce (Picea
mariana) Zones, where it is most abundant [
22].
Highbush cranberry has shown varying responses to overstory removal.
Near Prince George, British Columbia, highbush cranberry in white
spruce-subalpine fir (Abies lasiocarpa) forests had not become a
significant component of the vegetation 6 years after clearcutting,
although it was present on all sites prior to the harvest [
14]. In
Alberta, highbush cranberry had significantly lower cover in 6- to
12-year-old clearcut areas than in adjacent mature lodgepole pine
stands. In contrast, logging of a balsam poplar stand in Alaska caused
a dramatic increase in highbush cranberry density. It was one of the
dominant shrubs and reached 3.3 feet (1 m) in height within 4 years
[
22]. In general, frequency and cover are expected to remain constant
or decrease slightly in the first few years after overstory removal.
Vigor may increase slowly on favorable sites [
6].
Highbush cranberry is a seed-banking species, and soil disturbance
resulting from mechanical site preparation favors germination of stored
seed. The disturbance may also provide favorable seedbeds for freshly
deposited seed. Plants damaged in site preparation sprout from root
stocks and stem bases [
6].
Highbush cranberry increased less in a winter-logged balsam poplar stand
than in one that had been summer-logged. Higher soil disturbance on the
summer-logged site may have stimulated sprouting. However,
scarification did not enhance cover of highbush cranberry in clearcut
areas near Edson, Alberta [
22]. Highbush cranberry was also less
abundant on mechanically prepared sites than on unscalped sites in
interior Alaska. Frequency and cover of highbush cranberry 3 years
after clearcutting and shelterwood cutting of white spruce stands were
as follows [
63]:
Clearcut Shelterwood
scalped unscalped scalped unscalped
_____________________________________________________
Frequency (%) 13.3 38.3 13.3 20.0
Cover (%) 1.8 5.2 1.7 3.2
Highbush cranberry can be propagated vegetatively by hardwood or
softwood cuttings, although softwood cuttings are far more successful at
producing roots. Softwood cuttings root sooner and more prolifically in
sand than in perlite. Rooting success greatly increases by treating
cuttings with IBA (Indole-3-butyric acid). Rhizome cuttings also
successfully produce roots when planted immediately after fall
collection [
30].
Seeding may also be used for propagation of Viburnums. Seeds may be
broadcast sown on prepared seedbeds and mulched with sawdust or sown
with drills and mulched with straw. Seedlings may require shading,
depending on location. Fertile, moist soils which are neutral to
slightly acidic result in best germination [
21].
Herbicides can be used to control highbush cranberry. Glyphosate
exhibits good control and causes moderately severe damage to the plant
[
2,
22]. Aerially spraying a young aspen-balsam poplar stand in June
resulted in 95 percent defoliation and heavy mortality of highbush
cranberry [
22]. Roundup also causes defoliation and moderate mortality
rates [
6]. Hexazinone does not appear to control highbush cranberry
effectively [
2,
6].
Highbush cranberry is utilized heavily in tent caterpillar outbreaks
[
52]. Aphids, thrips, spider mites, and scale are also likely to occur
on Viburnums. A leaf spot (Ascochyta viburni) has been found on plants
along coastal British Columbia, and a rust (Puccinia linkii) has been
found on plants in northern British Columbia. Neither of these diseases
is considered serious [
22].
