BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Gaultheria procumbens | Wintergreen 



GENERAL BOTANICAL CHARACTERISTICS : 
Wintergreen is a spreading, evergreen, rhizomatous shrub which grows 4
to 8 inches (10-20 cm) tall [5,11,28].  Wintergreen creeps along the
ground, forming a dense carpet of shiny leaves that are 2 to 6 inches
(5-15 cm) long.  The small flowers are less than 0.5 inches (1.2 cm)
long and are borne at the base of the leaves [27].  The fruit is
berrylike capsule with a large fleshy calyx [45].  The roots are 1 inch
(2.5 cm) or less in depth [14,31].


RAUNKIAER LIFE FORM : 
   Hemicryptophyte
   Geophyte


REGENERATION PROCESSES : 
Reproduction in wintergreen is both sexual and asexual.  It typically
reproduces vegetatively from rhizomes.  Vegetative growth is initiated
as additional branching on old stems, or as new stems on creeping
rhizomes [55].  The long, infrequently branching rhizomes distribute
ramets over large areas; it exploits gaps in litter for clonal
propagation [23,50].  Bird-disseminated seeds are probably the source of
new plants colonizing old fields [32,41].

In the oak-pine upland forest of the Pine Barrens of New Jersey,
wintergreen occurrence was positively correlated (p<0.05) with the
presence of litter and dead wood [50].


SITE CHARACTERISTICS : 
As long as the soil is acidic, wintergreen grows well on many substrates
including peat, sand, sandy loam, and coal spoils.  It has been found
growing where soil pH ranged from 3.5 to 6.9 on the surface to 4.0 to
6.9 below the surface.  However, a pH of 4.5 to 6.0 has been reported as
optimum for growth, with 7.0 the maximum wintergreen tolerates.
Wintergreen mainly occurs on moist sites but tolerates moisture
conditions ranging from dry to poorly drained [2,32].

In jack pine communities in upper Michigan, wintergreen was present on
xeric, transitional, and mesic sites with frequencies of 11, 62, and 86
percent, respectively [3].  In Nova Scotia, wintergreen is found on the
tops of ridges and knolls in very shallow soil [58].


SUCCESSIONAL STATUS : 
Facultative Seral Species

Wintergreen is shade tolerant.  Fruiting, however, usually occurs in
openings [23,32,50].  It is a commonl understory species in the
Northeast [9].  In a Minnesota Norway pine (P. resinosa) forest,
wintergreen had greatest abundance of cover under intermediate light
intensities [56].

Wintergreen is found in the oldest vegetation in Grass River Bog, an
undrained sand plain in the Adirondacks [43].

Wintergreen is part of the understory vegetation in climax pine forests
of northern Minnesota [57].

In eastern hemlock (Tsuga canadensis) climax forest in northeastern
Pennyslvania, wintergreen frequency ranged from 0 to 6 percent [47].
 
In the Algonquin Provincial Park, Ontario, wintergreen was present in
early and climax stages of forest succession [49].  Frequency in the
birch-poplar (Betula spp.-Populus spp.) stage was 58 percent; it was
"abundant" in the pine stage.  Frequency was 36 percent in the
fir-spruce (Abies spp.-Picea spp.) stage.  Wintergreen was not present
in the sugar maple (Acer saccharum) stage, but frequency was 14 percent
in eastern hemlock climax forest [49].


SEASONAL DEVELOPMENT : 
Wintergreen flowers from the end of May to September depending on
geographic location [10,37].  In Illinois, wintergreen flowers initiated
during June open in mid-July, with the fruit maturing in September [45].
In New Jersey and Pennsylvia, the flowering period is from mid-July
through early August [55].  The leaves usually persist throughout the
winter [27,32].  The fruit may remain attached till the following spring
[45].

Related categories for Species: Gaultheria procumbens | Wintergreen