The rocky environments

There are many such environments spread throughout the park, usually above the timberline and the mountain pastures, and they are characterized by the constant presence of rock and detritus on the surface, resulting in a reduction of the ground layer: this makes life conditions very difficult, and alpine plants, here more than anywhere else, demonstrate their great ability to adapt, assuming characteristics (e.g. dwarfism, hairiness, bright coloured flowers, highly developed roots) which help them to survive in places where other species wouldn’t.

There are many types of detritus, which differ in the chemical nature of the rocks that they come from, in their texture (the size of their elements), in their stability or movement (sliding), and in altitude and exposure. In the park, detritus of shaly origin, characterized by fine, relatively damp material, is quite common. It is suitable for vegetation, although it can be quite unstable. Detritus or scree of silicolous origin, common mostly around the Gran Paradiso massif, constitute an environment of coarse material, where water is scarce, and in which only species well adapted to these conditions can grow (silicolous flora), just as with limestone detritus, which is decisively rarer in the park (calcicole flora).

Moraines, created by erosion, transportation and accumulation by glaciers, could be defined as cold, high-altitude detritus. The presence of the glacier guarantees a good level of moisture, at least at a certain depth, in contrast to the detritus which is arid both on the surface and underground. Moraines, too, are characterized by a substratum which is poor in organic substances, with coarse granules but less subject to landslides, (unlike detritus), and above all with a finer texture. However, the vegetation that colonizes the detritus and the moraines is more or less the same, influenced more by the mineral content of the substrate than by the rocky environment itself.

The rock faces or rocky slopes are also environmental typologies with extreme conditions for vegetation, which is influenced by the chemical nature of the rock, the exposure and inclination, and the presence of moisture; they can be seen quite frequently within the park’s territory at various altitudes, not just on the high peaks and snow covered mountains. Here, as with detritus and moraines, there are plants with particular morphological characteristics such as leading to pulvinus (cushion) from which only the flowering stalk extends, or long roots which can grow through the thin fissures in the rock in the search for water.