BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Vaccinium alaskensis | Alaska Blueberry 



GENERAL BOTANICAL CHARACTERISTICS : 
Alaska blueberry is a spreading to erect shrub reaching 6 feet (2 m) in
height.  Leaves are elliptic to obovate. The thin twigs are yellow green
but become gray with age.  The urn-shaped, bronzy-pink flowers are borne
singly in leaf axils when the leaves are partially developed.  The fruit
is a globose blue-black to purple berry that may or may not have a bloom
[4,32,33,55].

The plant is rhizomatous and generally has shallow roots.

Alaska blueberry is easily confused with ovalleaf blueberry.  These two
species can be distinguished by the fact that Alaska blueberry is taller
and has larger leaves than ovalleaf blueberry, and the latter flowers
before or with the leaves.  Alaska blueberry is also more shade tolerant
than ovalleaf blueberry [33,40,55].


RAUNKIAER LIFE FORM : 
   Phanerophyte


REGENERATION PROCESSES : 
Alaska blueberry is capable of reproducing by seed or by vegetative
means.  Vegetative reproduction is of primary importance to most western
Vaccinium species [39].

Seeds of most Vacciniums are not dormant and require no pretreatment for
germination [11].  A single Alaska blueberry fruit may have up to 100 or
more seeds [49]. The seeds germinate well, but seedling emergence and
survival are strongly correlated with the amount of available light
[29,49].  Seedling emergence in one study was 45 percent in
light-limited young stands, and 73 percent in older stands [49].
Germination on nurse logs is common [47].

Seeds are readily dispersed by the many birds and mammals that eat
Alaska blueberry fruits [3].

Vegetative reproduction:  Most Vacciniums regenerate from basal sprouts,
roots, or rhizomes [45].  Sprouting from branches or stems may also
occur after fire or herbivory.  Rhizome spreading allows for clonal
expansion, even in the absence of disturbance [49].


SITE CHARACTERISTICS : 
Alaska blueberry occupies a variety of different land forms from valley
bottoms to mountain slopes [16,21,22,30].  It is most often found in
cool, moist sites in montane forests [26].  These sites are generally
classified as moderately productive [8,26,27].  Alaska blueberry is
abundant on sites with minimal soil disturbance [2].  It is found at
elevations ranging from sea level to around 6,000 feet (1,800 m).
Aspect is variable [8,27].  Alaska blueberry can tolerate a wide range
of soil moisture conditions and is found in well-drained to poorly
drained sites [21,22,27,30].  Alaska blueberry has been classified as an
indicator of hypermaritime to maritime climates, and moist to very
moist, nitrogen-poor soils [34].

Alaska blueberry generally occurs in sandy, silt, or clay loams
developed in tephra and colluvial, morainal, or glacial till
[8,16,22,30].


SUCCESSIONAL STATUS : 
Alaska blueberry is capable of surviving many types of disturbance and
can be important in certain seral communities.  It can be an early
colonizer in clearcuts, burned areas, and in areas of windthrow [2,49].
However, as stands become dense and even-aged (stand age 25-150 years),
Alaska blueberry decreases drastically in frequency and abundance.  As
the stand continues to mature (stand age 150-250 years) and begins to
self-thin, Alaska blueberry again increases and forms a low, highly
branched layer [2].  Alaska blueberry is most often associated with
these late seral or climax community types.  It occurs frequently in
mature-climax western hemlock, Sitka spruce-western hemlock, coastal
true fir-hemlock, and Douglas-fir types [10,31,34,46,47].


SEASONAL DEVELOPMENT : 
Alaska blueberry flowers emerge from April to May after the leaves are
partially developed.  Berries ripen from mid-July to mid-August [55].

Related categories for Species: Vaccinium alaskensis | Alaska Blueberry