The tree line, also known as the timberline, is the elevation at which trees cease to grow. This boundary is determined by a combination of factors, including temperature, moisture, wind, and soil conditions. The tree line varies around the world, with higher elevations in tropical regions and lower elevations in polar regions. Above the tree line, the climate is too harsh for trees to survive, and the landscape is typically dominated by shrubs, grasses, and mosses. The tree line is an important ecological boundary, as it marks the transition between forest and alpine ecosystems.

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