BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Vaccinium pallidum | Hillside Blueberry 



GENERAL BOTANICAL CHARACTERISTICS : 
Hillside blueberry is a variable, erect, deciduous shrub that commonly
reaches 9 to 21 inches (23-51 cm) in height [14,48,61].  On some sites,
plants reach maximum heights of only 3 inches (8 cm), but on extremely
favorable sites, individuals may grow to 39 inches (100 cm) [61].  This
rhizomatous shrub forms small to extensive colonies [14,61].  The terete
to slightly angled twigs are pale green, reddish, yellow, or pale gray
[33,48,48,53].  The variable twigs are glabrous to pubescent [58].  Stem
morphology has been examined in detail [45].  Smooth, slightly ridged
bark is greenish-brown or red [53].  Roots are finely textured [20].

The simple, alternate leaves are variable in both color and morphology
[53].  Leaves are ovate, obovate, spatulate, or broadly elliptic and 0.8
to 2.3 inches (2.0-6 cm) in length [48,58].  Margins are entire,
minutely serrulate, or ciliate [53,58].  The glabrous upper surface is
yellow-green, pale green, or dark blue green, whereas leaves are paler
and glaucous to pubescent beneath [25,58,61].  Leaves turn scarlet or
crimson in the fall [33].

Cylindric to urceolate-campanulate inflorescences are borne in groups of
4 to 11 on axillary or terminal racemes [25,48,58].  The perfect flowers
are pink, greenish-white, or occasionally white [53,61] and average 0.25
inch (6 mm) in length [33].  Floral morphology has been reported in
detail [46].  Fruit is a sweet, juicy, globular berry 0.2 to 0.5 inch
(4-12 mm) in diameter [25,33,48,58].  Average berry weight has been
estimated at approximately 0.01 ounce (0.28 g) [3].  Berries are blue
and glaucous to black and shiny [25,61].  White-fruited forms, although
rare, have also been reported [33].  Each berry contains 8 to 14
variable, irregular seeds [25,53].  Of this number, approximately four
are viable [63].  Viable seeds tend to be brown or reddish-brown
[25,53].  The glossy, pitted seeds average 0.04 to 0.06 inch (1-1.6 mm)
in length [53].


RAUNKIAER LIFE FORM : 
   Chamaephyte


REGENERATION PROCESSES : 
Hillside blueberry can regenerate through seed or by vegetative means.

Seed:  In some areas, fruit is produced in abundance [33,53], but
elsewhere yields are more often small [16].  Vander Kloet and
Austin-Smith [63] reported that plants produce fruit "en masse" in the
Appalachians and Ozarks but produce fruit sporadically near the Atlantic
Coast.  Little is known about specific germination requirements.
Radicles generally emerge within 13 days, dicotyledons develop within 23
days, and true leaves are produced within 38 days after planting [60].
The seeds of most blueberries (Vaccinium spp.) germinate only on good
sites in favorable years.  Ballington and others [4] observed only a few
surviving hillside blueberry seedlings.

Vegetative regeneration:  Hillside blueberry spreads by means of rhizome
expansion to form extensive colonies [43,61].  Plants sprout readily
from underground rhizomes after aboveground vegetation is damaged or
destroyed.  Most rhizomes are concentrated in the top 1.9 inches (5 cm)
of the A horizon of the soil, but some extend to depths of 6 inches (15
cm) [10].  Buds nearest the stem apex typically sprout first after
disturbance [10].


SITE CHARACTERISTICS : 
Hillside blueberry grows on dry, rocky hillsides, upland ridges, rocky
outcrops and ledges, sandy knolls, and in shale barrens [14,58,61,53].
It commonly occurs on a variety of disturbed sites, such as abandoned
pastures and farmlands, along roadsides, and in clearcuts [14,44,58,61].
Hillside blueberry is a common component of dry, open woods but also
grows in hardwood swamps [51,61].  It generally occurs below 3,500 feet
(1,061 m) in elevation [14].

Soils:  Hillside blueberry grows on dry, sandy or gravelly soils, as
well as on heavy clay [17,25,30].  It grows well on acidic soils [53].
Parent materials are variable but include chert, granite, gneiss, and
schist [25,30].

Climate:  Hillside blueberry grows in a humid mesothermal climatic
regime [34].  Average annual precipitation amounts have been reported as
ranging from 39 to 47 inches (100-120 cm) [6,34,50].


SUCCESSIONAL STATUS : 
Hillside blueberry is reported to have "ruderale tendencies" [57,58].
It commonly invades disturbed sites, such as abandoned farms and
clearcuts [58,61].  In parts of New England, it has become widely
established on abandoned pasturelands.  Hillside blueberry, black
huckleberry, and roundleaf greenbrier (Smilax rotundifolia) have assumed
dominance in these relatively stable plant communities [44].  In many
areas, it becomes more abundant on plots burned at frequent intervals
[27].

Hillside blueberry also grows in several climax communities.  It occurs
in climax stands in pine-oak communities of New Jersey and in old-growth
post oak-black oak communities of the South Carolina Piedmont [30,37].


SEASONAL DEVELOPMENT : 
Flowers generally appear before the leaves are "half grown" [33].  The
mean interval between flowering and fruiting is approximately 66 days
[24].  Vander Kloet [61] reported a period of 60 days until seed set.
Hillside blueberry often ripens over a relatively long period of time
[53], although much geographic variation has been observed.  In the
foothills of the Appalachian and Ozark mountains, populations often
fruit synchronously [63].  However, in coastal regions, fruit ripens
sporadically [63].  Ballington and others [4] observed peak ripeness in
early June, although berries could be harvested from July 12 to July 29.
Generalized flowering and fruiting dates are as follows:

Location             Flowering          Fruit ripe        Authority

  VA                    ----           July - August      Uttal 1987
Great Plains        April - June       July - September   Great Plains Flora
                                                            Flora Assoc. 1986
n-c Great Plains    mid-April          early July         Stephens 1973
NC, SC              March - April      June - July        Radford and others
                                                            1964     
   OH                   ----           July 16-28         Gorchov 1987
New England         May 10 - June 14        ----          Seymour 1985  

Related categories for Species: Vaccinium pallidum | Hillside Blueberry