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Illustrated on this page are
wildflowers that grow in the Rocky Mountains, from Waterton National
Park to northern Yukon. Many of the plants illustrated were
photographed in the alpine and subalpine. Although focusing on
the Alpine and Subalpine subzones, wildflowers illustrated on these
pages may occur in several subzones. The species illustrated is
not comprehensive. The intent is to illustrate only a few of the many
species that occur in the Rocky Mountains.
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Here for Rocky Mountain Wildflowers
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Here for Yukon Alpine Wildflowers
The Rocky Mountains consist of a
variety of terrains, each with topographically different
conditions. Major valleys run parallel to the mountain
ranges. Mountain drainage systems allow water from mountain
glaciers and snow packs to drain into the valleys. The Rocky
Mountains trend along the western part of Alberta and form the
Continental Divide. In Alberta, the Rocky Mountains range in
width from 10 km in the Waterton Lakes National Park area to more
than 100 km in the central portion. Elevations rise from east
to west, reaching a height of about 3700 metres along the Continental
Divide. The highest mountains occur in the central part of the
Region with the lower mountains in the far north and far south.
The Rocky Mountains are
distinguished from the Foothills of Alberta by the differing geology.
The Rocky Mountains consist primarily of deformed carbonate and
quartz-rich (quartzite) rock. The Foothills consist primarily
of deformed sandstone and shale.
Within the Rocky Mountain region,
three natural subregions exist: Montane, Subalpine and Alpine.
Montane Subregion:
Much of the southerly portion of
the Montane Subregion occurs on east-west trending ridges that extend
out from the Foothills Belt from the United States border. The
Montane subzone marks the beginning of mountain forests.
Sandstone outcrops are typical of the main, southerly portion.
Elevations range from 1000-1350 metres in Jasper National Park, to
1350-1600 metres in Banff National Park, to more than 1600 along the
Eastern Slopes south of Calgary.
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Here for Rocky Mountain Wildflowers
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Subalpine Subregion:
Typically, the Subalpine
Subregion is intermediate between the Montane, or the mountain forest
subregion, and the treeless alpine subregion. The Subalpine
subregion is cooler and wetter than the Montane and lower zones.
The upper limit of the Subalpine Subregion ranges from about 2300
metres in southern Alberta to about 2000 metres in northern
Alberta. The lower limits of the Subalpine Subregion range from
about 1600 metres in the south and 1350 metres in the north.
These conditions support white and Engelmann spruce, subalpine fir
and five-needle pines. Lodgepole pine replace the spruce and
fir stands after forest fires. Shrubs typical of the subalpine
region include: false azalea, Labrador Tea, bracted honeysuckle, rock
willow, and Canada buffaloberry. At higher elevations, where
winds are stronger and intense sun increases moisture stress,
Engelmann spruce and subalpine fir dominate. Ultimately,
subalpine merges with the alpine subzone and tree cover becomes
sparse and characterized by asymmetric tree shapes called kruppelholz
(a German word meaning "crummy wood") or elfin
wood-shapes. The elfin wood shape is bent to assume a
horizontal shape. Melting snow pack commonly maintains water
flow in creeks or small rivers throughout the summer.
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Here for Rocky Mountain Wildflowers
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The Alpine Subregion:
The Alpine Subregion is the highest
vegetative zone , above the treeline, with level to steep
slopes. Extensive areas of unvegetated bedrock occur. Rock
glaciers occur in some areas, such as Kananaskis Country and
northward to Jasper National Park.
Wildflowers grow on thick sod grasses and sedges. The subregion
may have permanently frozen soil characterized by low-growing
vegetation such as lichens, mosses, tussock grasses and stunted
shrubs. The land is generally rocky, with sparse soil, exposed
windswept ridges, level to steep slopes. The subregion is
colder and has a shorter growing season with longer, harsher winters
compared to the other subregions. Summer temperatures may
occasionally dip below freezing. Wildflowers bloom during the
longer days of summer - mid-June to mid-July. Plant diversity
is determined in part by snow cover, soil development and type, snow
melt patterns, and wind exposure. The main flowering period is
June and July, although the same species may be seen in different
states of flower development by traveling up-elevation.
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Here for Rocky Mountain Wildflowers
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Here for Yukon Alpine Wildflowers
Wildflower
Adaptations for Harsh Conditions of the Subalpine and Alpine Subregions:
Wildflowers
that grow in the Subalpine and Alpine Subregions evolved several
adaptations to accommodate in an environment characterized by strong
and desiccating winds, abundant sunlight and intense solar,
ultra-violet radiation, wide fluctuations in temperature, and low
moisture capacity of the sparse soils. Most flowering plants
are perennials to accommodate the short and harsh growing
season. Major adaptations reduce evapouration of scarce water
from the plant. This adaptation is accomplished by having:
-
a waxy leaf surface;
- special
stomata that open at night when the temperature is cooler and loss of
water vapour is less;
- dense
pubescence, or hairs, that reduce wind-driven evapouration and act as
a sunscreen that filter out harmful solar radiation;
- a
preference to grow in crevices;
- a compact
or cushion growth shape;
- deep and
strong roots to find limited soil nutrients and moisture;
- large
flower structures and dwarf vegetative parts.
Microhabitats:
Despite the
generalities described above, many areas are characterized by quite
different growing conditions, while coexisting side by side.
For example, south-facing zones lose their snow cover early and
flowering starts early in the warm sunlight. A north-facing
valley may keep its snow cover late into the summer. The
contrasting habitats is called microclimate.
Click
Here for Rocky Mountain Wildflowers
Click
Here for Yukon Alpine Wildflowers
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