baumzaehlen - Primeval Forests & Their Trees

©2019copyright christoph hase

Wasserkar Primeval Forest, Austria


One could think the largest primeval forests of Central Europe would be located in the high altitudes of the Alps. However, the high altitude regions were already settled in the Bronze Age; extensive deforestation happened between the 8th and 14th centuries 1. Wasserkar in the Blühnbach Valley is a very rare example of subalpine virgin forest with Opens internal link in current windowLarix decidua (European larch).


The reserve (35 ha 2), particularly its upper part, is very difficult to reach. As parking along the road running through the valley is not allowed without a special permit, an 11 km hike from Tenneck is first needed. The primeval forest is not marked in any way. It is located on a north-facing steep slope that is possible to reach from the north. From all other directions the forest is protected by high cliffs. There may have been wood extraction in the past from the lowest part of the reserve; at least trees felled by wind were removed2. Ascending further, however, there is a very steep rockslide passable at only a few points. Low Pinus mugo (dwarf mountain pine) thickets grow on these very steep rocky sites, making the access even more difficult. The rockslide has protected the upper parts of the reserve, which are virtually untouched2. For pasturing, the area was too small2.


The slope is slightly less steep above the rockslide. Opens internal link in current windowPicea abies (Norway spruce) dominates up to 1350 m, then P. abies together with L. decidua, and from 1550 m up to the tree line at 1700 m L. decidua dominates alone2. There is abundant P. abies regeneration in the L. decidua forest, too, but it is not capable of developing further due to the cold climate2. There are also a few Opens internal link in current windowSorbus aucuparia (European rowan) and Opens internal link in current windowAria edulis (syn. Sorbus aria, whitebeam). Pinus cembra (Swiss pine), a common companion of L. decidua 3, is missing here2.


When planted in lowlands, L. decidua is one of the tallest European tree species, with heights up to 53.8 m 4. However, in its native range L. decidua never occurs in its optimal growing conditions; the natural L. decidua forests exist simply because the species resists the harsh climate better than the other trees3. In Wasserkar L. decidua reaches approx. 30 m in height. The forest is open with abundant windfalls.


Browsing of chamois and red deer is severe2 and their traces and paths are abundant. On the contrary, human traces are entirely absent. Annual precipitation is approx. 2300 mm, with a summer maximum, and the average annual temperature (probably in the lowermost part) 4°C 2. The soil is lime rich2.




1       Parviainen, J. (2005): Virgin and natural forests in the temperate zone of Europe. For. Snow Landsc. Res. 79, 1/2: 9–18.

2       Mayer, H. & Wallmann. R. (1987): Der Urwaldrest Lärchenwiesenwald im Wasserkar (Blühnbachtal). In Mayer. H. (ed.): Urwaldreste, Naturwaldreservate und schützenswerte Naturwälder in Österreich. Institut für Waldbau, BOKU.

3       Ellenberg, H. (1996): Vegetation Mitteleuropas mit den Alpen. Ulmer.


Picea abies (Norway spruce, with dense foliage) and Larix decidua (European larch, e.g. extreme left).
Larix decidua (European larch, taller trees), Picea abies (Norway spruce, saplings) and Aria edulis (syn. Sorbus aria, whitebeam).
Picea abies (Norway spruce, dark green foliage) and Larix decidua (European larch, light green foliage) behind windfall.
Larix decidua (European larch, with light green foliage and foreground left), Picea abies (Norway spruce, with dark green foliage).
Wasserkar from distance. Larix decidua (European larch, light green crowns) and Picea abies (Norway spruce, dark green crowns). The rockslide (see the text) visible at the bottom.
A part of the reserve from below. Larix decidua (European larch, light green crowns) and Picea abies (Norway spruce, dark green crowns).