Timberline / treeline

Timberline / treeline reference article on thruhikingwiki.com.

Overview

Timberline or treeline marks the elevation or climatic boundary above which trees cannot grow due to environmental conditions such as cold temperatures or strong winds.

Key points

  • Represents the upper limit of tree growth in mountain environments.
  • Above this line, vegetation shifts to alpine tundra.
  • Influenced by climate, aspect, and regional weather patterns.
  • Often subject to extreme winds and rapid weather changes.
  • Important for route planning in exposed terrain.
  • Provides visual cues about elevation and environmental zones.

Details

Treeline varies by latitude, regional climate, and local topography. In many mountain ranges, the transition is gradual, marked by krummholz—stunted, wind-shaped trees—before giving way to open alpine landscapes.

Above treeline, hikers encounter exposed terrain where weather can change rapidly, winds are stronger, and shelter options are limited. Understanding treeline helps hikers identify ecological transitions and prepare for more extreme conditions.

Treeline zones influence route choices, campsite availability, and risk of storms.

Illustrative hiking footage

The following external videos offer general visual context for typical hiking environments. They are not official route recommendations, safety instructions, or planning tools.