GEOG 2152: Geography of Hazards
Reading #5 Review Questions
1. How has the elimination of some forest fires contributed to the mountain pine beetle problem
in British Columbia?
British Columbia’s forests were packed with three times as many mature pines as
there would have been had they been allowed to burn naturally. It turned the woods
into beetle buffets.
2. What is the reason that some scientists believe that the beetle could potentially spread all the
way to the Atlantic provinces of Canada?
Because the beetle is already in jack pines, and jack pines live as far east as Nova
Scotia and down into the upper Midwest and New England.
3. In the past, the relationship between beetles and the forest was considered mutually
beneficial. Explain how that has changed in recent years.
The human activities warmed the whole planet with our carbon dioxide emissions.
Rising temperatures and drought have stressed tress, leaving them unable to fight
an invasion. The trees like jack pine and whitebark are not as good at defending
themselves, a small band of beetles can overwhelm them.
Warmer weather also had boosted the beetle’s population and greatly expanded
their range to farther north and at higher elevations.
4. Describe how female beetles have evolved to survive the natural defenses that the trees
When a female mountain pine beetle lands on a tree, she first decides whether it is
a decent place to raise a family. To do this, she will chew into the bark and taste
the chemicals. If the tree meets her standards, she will continue burrowing,
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