The Arctic willow or Salix arctica is a resident of the North American Tundra and has adapted to the weather conditions of this region. The Arctic willow forms a pesticide to keep the predator insects (such as the Arctic woolly bear) away. Since rainfall is extremely low (6-14 inches annually) in these regions, the Arctic willow survives by possessing a shallow root system, which allows it to absorbs soil moisture at shallow depths. Such a shallow root system also helps the growth of these plants in permafrost. To protect itself against the cold weather, the Arctic willow has adapted by growing long fuzzy hairs and growing close to the ground. Such adaptations protect the plant from winds. These plants grow like a carpet gaining the heat energy from the ground and protecting themselves from the cold weather in tundra regions.
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