tree line; timberline; forest line
Geographical term for the elevation or latitude beyond which trees cannot grow. Used in ecology, geography, and mountaineering contexts.
富士山の森林限界は標高約2400メートルです。
The tree line on Mount Fuji is at about 2,400 meters above sea level.
森林限界より上では、木はほとんど見られない。
Above the timberline, trees are rarely seen.