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tree line

Wikipedia

tree line (plural tree lines)

A division in altitude (or latitude) above which trees tend not to grow on mountains.
- 1957 August, H. A. Vallance, “By Rail to the Norwegian Arctic”, in Railway Magazine, page 575:
  Snowsheds and snow fences protect the line on either side of Semskfjell, but the country soon begins to lose some of its bleakness, and the tree line is regained at Lønsdal (1,680 ft. above sea-level), where the line is high on a hillside, commanding widespread views of the mountains.

Translations

Catalan: límit forestal m, límit arbori m
Danish: trægrænse (da) c
Finnish: puuraja (fi)
German: Baumgrenze (de) f, Waldgrenze (de) f
Japanese: 森林限界 (ja) (shinringenkai)
Korean: 삼림한계선(森林限界線) (samnimhan'gyeseon)
Norwegian:
Bokmål: tregrense (no) m or f

Nynorsk: tregrense f
Persian: دارمرز (fa) (dârmarz)
Polish: granica drzew f
Portuguese: linha das árvores f
Russian: граница древесной растительности f (granica drevesnoj rastitelʹnosti), граница леса f (granica lesa)
Serbo-Croatian: rub šume m
Swedish: trädgräns (sv) c