BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Vaccinium caespitosum | Dwarf Huckleberry 



GENERAL BOTANICAL CHARACTERISTICS : 
Dwarf huckleberry is a dwarf-to-low, spreading, rhizomatous shrub
[34,71,80,81].  This often mat-forming shrub grows 2 to 20 inches (5-50
cm) in height [34,55,71,81].  Twigs are much-branched, angled, glaucous,
and glabrous to puberulent [55,81,85].  When young, twigs are green,
tannish, or reddish, but with age twigs become brown or brownish-gray
[71,81].  The shreddy bark is yellowish-green, green, or reddish
[34,73].  Roots of the dwarf huckleberry are fibrous and spreading [73]
and reach depths of 0 to 67 inches (0-170 cm) [57].  Plants are
relatively short-lived [73].

The deciduous, alternate leaves are elliptic to oblanceolate or obovate,
and widest well above midlength [40,47,60,71].  Leaves are acute or
rounded at the apex, entire, crenulate or serrulate from the tip to
middle, and 0.4 to 2 inches (1-5 cm) in length [34,73,84,85].  The upper
surface is bright green and glabrous, whereas the lower surface is
glandular and a paler, light green [30,34,81].

Flowers are urn or bell-shaped and borne singly in the axils of leaves
[41,55,60].  The small, inconspicuous, waxy flowers are pink, white, or
red [41,73,77].  Floral morphology of the dwarf huckleberry has been
considered in detail [59].  Fruit is a subglobose to globose berry which
averages 0.2 to 0.8 inch (5-8 mm) in diameter [34,55,85].  Berries are
dark blue to black with a glaucous bloom [47,71,85].  Fruit is sweet
[34] but generally not produced in abundance [80].  Berries contain
small, brown, cellular-pitted seeds [55,72].


RAUNKIAER LIFE FORM : 
   Phanerophyte


REGENERATION PROCESSES : 
Dwarf huckleberry reproduces both sexually and vegetatively, although
vegetative regeneration appears to be of primary importance.

Seed:  Vaccinium seeds are not dormant and require no pretreatment for
germination.  Seedlings first emerge within 1 month after seeds are
planted, and germination continues over a long period of time if no cold
stratification is provided.  Germination capacity of dwarf huckleberry
in laboratory tests was estimated at 96 percent [15].  Berries are
sweet, nutritious, and highly attractive to mammalian dispersers.
Colorful berries are also consumed in great numbers by both year-round
resident and transient breeding birds which can effect long-distance
dispersal.  The tough seeds generally pass through digestive tracts
undamaged [72].

Dwarf huckleberry seedlings are rarely observed under natural conditions
in the West.  Germination may be limited to exceptional sites in
favorable, moist years.  Seed stored on-site appears to contribute
little to regeneration of this species [37].  Buried seeds have been
recovered from the top 1.2 inches (3 cm) of soil in balsam fir (Abies
balsamea)-white spruce (Picea glauca) forests of Quebec, but viability
was very low (0-16 percent) [53].

Vegetative regeneration:  Dwarf huckleberry is rhizomatous [55,71,80]
and plants are often capable of resprouting after the crown is removed
or damaged.  However, these regenerative structures are fairly shallow
and can be damaged or eliminated by deep, duff-consuming fires or
mechanical treatments which include severe soil scarification.  Twigs
are capable of regenerating at the nodes [81] and vegetative expansion
can occur even in the absence of disturbance.


SITE CHARACTERISTICS : 
Dwarf huckleberry occurs at the margins of subalpine meadows, in
mountain ravines, along riverbanks, near snowbanks, or along the shores
of ponds and bogs [55,56,68,71,74,81,84].  It commonly grows on moist
subalpine or alpine slopes and on mossy forest floors where it
frequently forms a low, nearly continuous layer [41,84,85,46].  Dwarf
huckleberry is particularly abundant on flat terraces, benches, or
basins subject to frost [13,38].

Soils:  Dwarf huckleberry grows well on medium-coarse, well-drained,
granitic soils [73,79].  Most huckleberries (Vaccinium spp.) require
acidic soils and can grow on infertile sites which have relatively small
amounts of many essential elements [43].  Dwarf huckleberry commonly
occurs on soils with a pH of 5.5 to 7.0 [73].

Elevation:  Dwarf huckleberry extends through the subalpine zone to well
above treeline [33].  In eastern North America, it typically occurs at
higher elevations [68].  Generalized elevational ranges by state are as
follows [18,55,81,85]:

                     to 3,800 feet (1,200 m) in AK
                   from 7,000 to 12,000 feet (2,134-3,660 m) in CA
                        8,000 to 12,000 feet (2,438-3,660 m) in CO
                        3,500 to 10,000 feet (1,067-3,048 m) in MT
                        7,300 to 10,363 feet (2,225-3,420 m) in UT
                        8,500 to 10,600 feet (2,591-3,233 m) in WY 


SUCCESSIONAL STATUS : 
Dwarf huckleberry occurs in climax Douglas-fir or spruce-fir forests
throughout much of the West [54,67].  However, it is also considered an
important seral shrub in many areas of western North America [26].  An
extensive network of shallow rhizomes enables this shrub to rapidly
reestablish after most light to moderate disturbances.


SEASONAL DEVELOPMENT : 
Dwarf huckleberry flowers in late spring or summer with fruit maturation
beginning immediately after flowering [72,79].  Fruit ripens in mid to
late summer or fall, and seed dispersal occurs from July to September
[72,73].  Leaves drop in early autumn [40].  However, specific
phenological development varies annually according to weather
conditions.  Seasonal development in various geographic locations has
been documented as follows [18,53,55,60,68,81]:

     location             flowering               fruiting

       AK                 late May-mid July       August
       CA                 June-July               -----
       CO                 July                    -----
     n ID                 May-July                -----
     New England          June 1-June 27          -----
       PQ                 June-July               July-September
       UT                 June                    -----

Related categories for Species: Vaccinium caespitosum | Dwarf Huckleberry