Changing Planet: Bark Beetle Outbreaks
Bark beetles are native to North America. They are about the size of a grain of rice. They've always been an important part of the forest ecosystem, and despite their size, they work aggressively together to eliminate weakened trees, so new, more vigorous trees can grow in their place.
Currently, there is a major outbreak of bark beetles in the southeastern U.S. (mainly the Southern pine beetle Dendroctonus frontalis) and the western U.S. and Canada (mainly the mountain pine beetle Dendroctonus ponderosae). The mountain pine beetle alone has been charged with killing about 47 million hectares of trees! Though bark beetles live in other places like Europe, Asia and Africa, and there have been bark beetle outbreaks before, the U.S. is experiencing an unprecedented outbreak level. Some scientists worry that the trees of the U.S. won't be able to recover from this epidemic. Others see this outbreak as a natural ecological development that needs no human intervention because it will right itself. Find out more for yourself by exploring the Bark Beetle video and classroom activity.
Click on the video at the left to watch the NBC Learn video - Changing Planet: Bark Beetle Outbreaks.
Lesson plan: Changing Planet: Bark Beetle Outbreaks
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