| Zusammenfassung: | On the basis of observations made on a one-day field excursion to Marmot Creek and Plateau Mountain in the Canadian Rockies, the author outlines the principal features and compositions of the timberline. These aspects are compared with those of Central Europe, especially the Czechoslovakian Carpathians. Timberline trees in the visited areas in Canada are Picea engelmannii, Abies lasiocarpa, Larix lyallii, and Pinus albicaulis; in Central Europe they are Picea excelsa, Larix decidua, and Pinus cembra. Local conditions dictate the dominant timberline species. The form of tree regeneration also influences the nature of the timberline. In the region of the upper timberline the forest growths are regenerated most often by branches touching the ground. In the place visited in the Rocky Mountains above the upper timberline the species which occur only in shrub form are missing. Therefore, the forest growths are gradually changed into shrub without breaking the crown cover. In Central Europe the branches of the shrub Pinus mugo ssp. mughus lie on the ground and prevent the branches of spruce (Picea excelsa) from touching the ground and rooting. Since the generative regeneration from seeds is low, the tree forest growth disintegrates into tree groups.
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