Not far from the Lenne, a spring creek has cut into the rock, creating a different little world with remarkable flora and fauna and a quiet aesthetic all its own. Recreation is offered by the protected notch valley with its impressive rocks, numerous rapids and small waterfalls. Broom bushes, birch trees and blueberry bushes constantly break up the shady spruce, beech and oak forests. Admire the large ferns and diverse moss species that cover the forest floor like a carpet and the rich fauna with fire salamanders, small woodpeckers, frogs and more than 900 species of beetles. Imposing cliffs on the steep forested mountain slopes and numerous rock steps in the creek give the valley its canyon forest character. In the lower part, the stream bubbles over rocky banks, forms rapids and whirlpools. Finally, the stream roars down through a narrow, shady gorge.
Bommecke means "stream surrounded by trees" - and that is exactly what a walk through the Bommecketaloffers: wild forests and lots of water.
Habitat for species from much higher altitudes
The Bommecke is the preferred habitat of species that depend on cool, very clean water with a high oxygen content. These are rare, often inconspicuous species such as stream cap snails and spring snails, alpine planarians and eyelid midges and their larvae, or certain mosses tied to torrents. A rare crustose red alga forms extensive blood-red beds on alternating wet rock in the Bommecke and some spring creeks. Due to the canyon-like character of the north-exposed notch valley, species are found that normally only have their home at much higher elevations. Meanwhile, the valley has become a refuge for a variety of montane species.
Character animal with year-round habitat there is the fire salamander. Its larvae grow in the clear mountain waters. It also hibernates in the old mine tunnels, as do several species of bats. Gelappter shield fern and spotted fern typically grow on the rocky ledges. Bird species typical for the Bommecketal are the water ouzel and the grey wagtail.