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The Evergreen
Coniferous Forest
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Evergreen
coniferous forests, which are also called tiaga, begin where
tundra gives way to trees. These forests grow over a large area
of earth's land, extending toward warmer regions. The climate
in evergreen forests is pleasant in summer, when temperatures
may rise into the eighties and evenings are cool. Winters, however,
can be very cold, dropping to -65 degrees Fahrenheit in some
areas, but barely falling below freezing in others.
Rainfall in this biome
varies from 12 to 33 inches a year. Some of this moisture comes
in the form of snow, and sometimes young trees are buried by
snow in the winter. This covering of snow protects the trees
from intense cold and dehydration by icy winds.
| Mountain
sides are often covered by coniferous forests. The trees are
tall and narrow, so that the snow will slide off the branches
without breaking them. The trees grow close together, protecting
one another from the wind. Their tough green needles last for
more than one year. Needles resist frost and wind damage and
conserve water while while making food through photosynthesis.
They are ready to go to work as soon as the weather is warm enough.
The trees also have thick bark that resists damage from summer
fires. |
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These evergreen trees make seeds in
cones, and use the wind for pollination. The close-set trees
make wind pollination efficient. In the spring the air is often
golden with floating pollen that is released from the pollen
cones.
Evergreen trees developed on earth
long before there were any flowers. Coniferous trees, ferns,
and mosses are ancient plant families. Their ancestores were
nibbled on by dinosaurs!
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There are other plants
in this biome. Grass grows here and there under the trees where
the ground is dry and there is enough sunlight. In moister, more
shaded areas, there are ferns and mosses. There are wild flowers,
and a variety of deciduous bushes of various sizes. Fungi grow
on fallen trees and help old needles and twigs to decompose. |
Animals must deal with the hardships of
long, cold winters. Birds with strong beaks hunt for insects
and pine nuts: squirrels scamper in the branches. Insects abound
in the summer and winter over as eggs or grubs in the trees.
Many birds leave when the cold weather comes: some animals hibernate.
Porcupines continue to gnaw on the trees. The largest herbivores
are deer, who can travel far in search of food. A few cougars
hunt the deer.
Photographs from Corel CD-ROMs: for viewing only,
not for downloading. More
Information.
© 1998. Elizabeth Anne Viau. All
rights reserved. This material may be used freely for instructional
purposes but not sold for a price beyond the cost of reproduction.
Please inform the author if you use it at eviau@earthlink.net
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