On a bright summer day I
like to start in a low elevation forest and hike up to the summits. Starting a
hike at low altitude adds several components to the trip. You need to start
earlier in the day in order to reach your destination and return. Consequently
you get more exercise, more of a workout because of the greater elevation gain,
and spend more time in the outdoors. There are also components other than those
associated with the exercise. There are the changes to be seen between the base
of the mountain and the peak.
In coastal British Columbia there is a considerable difference in the vegetation
at sea level and that on the mountain crests. Even if you do not know their
names, when you look at the trees you will see that those growing on the peaks
are different. The low altitude forests are mostly western hemlock (Tsuga heterophylla). They grow close
together, and their thickly clustered needles stop most of the sunlight from
reaching the ground. It is a shady, cool walk to start the day. Associating
with the western hemlock are Douglas fir (Pseudotsuga
menziesii), and western redcedar (Thuja
plicata). Because of the dominance of western hemlock, these forests are
called the Western Hemlock Zone.
As you ascend the slopes you
will see that the lower elevation kinds of trees are gradually replaced by
different types of trees. This transition begins around the 1000 metre level.
By the time you reach 1200 metres almost all the trees are different species
from those down below. This is called the Mountain Hemlock Zone because
mountain hemlock (T. mertensiana) is the dominant tree, replacing the lower
elevation western hemlock. Red cedar is replaced by yellow cedar (Chamaecyparis nootkatensis), and Douglas
fir gives way to amabilis fir (Abies
amabilis).
When you proceed further not
only are the trees different, they are also farther apart, with little seepage
areas covered by grass-like sedges. Some of the ponds are rimmed with
cotton-grass (Eriophorum angustifolium),
which is actually a sedge, not a grass. Sedges are related to grasses, but
belong to a different family. Most of the grasses in marshes are actually
sedges. Cotton-grass has fluffy seed heads, like balls of cotton. The white
edges of these ponds can be spotted from a long distance away. Higher up are
the open rocky summits with little soil and few trees. From such vantage points
you can look down on the route your journey has taken earlier in the day. Above
1500 metres are extensive meadow slopes clothed in wildflowers. These are the
subalpine meadows. Scattered here and there are small clumps of little trees.
Higher still the trees give out all together. The slopes and flat areas are
covered with alpine flowers, whereas the rocky ridge crests are covered by
heathers, with small, needle-like leaves. They look more like little conifers
than flowering plants. The reason they have needle-type leaves is the same
reason that conifers have them - to conserve moisture.
The lower forest is the
rainforest, or at least on the outer coast it is a rainforest. In the Lower Mainland
area it does not get quite enough moisture to be a true rainforest, but the
plants are essentially the same in both areas. The most noticeable difference
is the mosses. They are more luxurious in the true rainforest. The most
striking is the cat-tail moss (Isothecium
myosuroides). In humid places it hangs from the trees in long, thin
streamers. The sea level forest is wet
and snow free for most of the winter. Except for the driest part of the summer,
the evergreen trees and mosses continue to grow right through the year. The
upper areas are the snow forest. The snow comes to the summits in October and
does not completely leave until July. This means that even after the warm
spring sun shines on the tree tops, and brings re-growth to the mosses and lichens
growing there, the ground remains in winter right into the early summer. The
plants found here have only four months to grow, flower, and set seed. Most of
our familiar plants cannot survive under such extreme conditions. This is the
land of the heathers, and alpine meadows. It is a land quite different from our
familiar woodlands, a land where we are just casual visitors. We spend the day
struggling upwards, stop a few fleeting minutes on the peak, and then return to
our homes in the lowland.
Even though you may not know
their names, if you look at the mosses of the forest floor you will see that
they too change as you ascend the slopes. The most common moss on the ground at
low elevations is the Oregon
beaked moss (Kindbergia oregana). It
is shaped like a little green feather, and forms dense carpets. Also common is
a pale green species - wavy leaved cotton moss (Plagiothecium undulatum). It is closely appressed to the surface
and looks superficially similar to a delicate cedar twig. Also forming thick
carpets is the step moss (Hylocomium
splendens). It is called step moss because it forms a new step-like shoot
each year, and you can count each previous year’s growth, something like
counting tree rings. When you get to about the thousand metre level the ground
between the blueberry bushes is often densely clothed with a completely
different moss, one with shaggy, wrinkled leaves. Because of this appearance it
is called pipecleaner moss (Rhytidiopsis
robusta). The appearance of pipecleaner moss tells us we are approaching
the summits.
With the coming of spring,
memories of summer hikes return, and anticipation of seeing the mountain plants
re-awakens. Even if it is a peak that has been visited many times, there are
still new experiences to be had, and new things to be seen. As the snow melts
back the high altitude plants, which are cold resistant, push through its
edges. To see these emerging shoots is to see the emergence of summer. They say
in their own way that for a few months life has again returned to the high
country.
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