|
|
The Maritime Barrens Ecoregion extends from the east coast of Newfoundland to
the the west coast through the south central portion of the island. This
ecoregion has the coldest summers with frequent fog and strong winds. Winters
are relatively mild with intermittent snow cover particularly near the
coastline. Annual precipitation exceeds 1250 mm.
The landscape pattern consists of
usually stunted, almost pure stands of Balsam Fir, broken by extensive open
heathland. Good forest growth is localized on long slopes of a few protected
valleys. The development of the extensive heath landscape was precipitated by
indiscriminate burning by European settlers. Railways in the nineteenth century
also had a significant impact on fire frequency in the eastern part of the
region. The heaths are dominated by Kalmia angustifolia on protected
slopes where snow accumulates and by cushions of Empetrum nigrum or
Empetrum easmesii on windswept ridges and headlands.
Attemps to afforest these heaths with
Picea sitchensis have been unsuccessful, but Eastern larch and Scots Pine
may have potential for fuelwood stands (Hall 1986). However, site selection is
critical because the historical removal of forest has deflected the natural
treeline to low elevations. Wind, lack of protective snow cover and soil frost
disturbance are important factors limiting plantation establishment in this
ecoregion.
A. Northeastern Barrens Subregion
This subregion has lower fog frequency and
somewhat warmer summers compared to subregions B and C. Arctic-alpine species
are absent from the heath vegetation and Yellow Birch is absent from the forest.
The landscape is extensively forested with local heath vegetation particularly
along the coast.
The tills in the area are generally a
shallow rolling ground moraine with sandy loam to loam texture. The
Hylocomium-Balsam Fir type occupies mid-slopes and it is usually associated with
gleyed podzols or gleysols.
B. Southeastern Barrens Subregion
In this subregion the landscape is
dominated by heathlands and the forest only occurs in small acreages which
escaped fire. The dominant heath shrub on uplands is Empetrum nigrum with
Kalmia angustifolia forming a dense cover only in protected
valleys.
The topography is generally undulating
with shallow heavily compacted till and numerous large erratics. The
Clintonia-Balsam Fir type is most common where the forest is still present. Good
forest growth only occurs in a few large protected valleys where the
Dryopteris-Balsam Fir type dominates the slopes. Good specimens of Yellow Birch
are also found in these stands.
C. South Coast Barrens Subregion
This subregion includes the higher
elevations along the south coast and a few small outliers on the isthmus of
Avalon and the Hawke Hills that are up to 300m in elevation. Snow cover is
shallow and arctic-alpine plants occur locally. Yellow Birch is present in
valleys.
D. Central Barrens Subregion
This area occurs south of the Central
Newfoundland Ecoregion and north of the South Coast Barrens Subregion. Residual
forests that have not been destroyed by fire have moderate forest capability.
The dwarf shrub heaths are robust and Rhododendron canadense is a
conspicuous component suggesting deep snow cover. Arctic-alpine species are
poorly represented and Yellow Birch is absent from the forest.
|
