The cliffs or the rocky walls can be seen everywhere in the Park, at different altitudes and not only on alpine and snowy plains. As it happens in the above-mentioned humid environments, we can find plants with peculiar morphological features such as cushion-like bearing which leaves just the flower scape exposed. They also have long root systems, capable of developing among the thin cracks of the rock in search of water.

THE PRAIRIES

In the Park, there are also several steppe grasslands, meadow-pastures, high-altitude alpine pastures, and snowy valleys.
The steppe grasslands are made of herbaceous plant formations (grass) and a few dicotyledons, especially in the area facing Valle d’Aosta; they can be found at relatively low altitudes and are used for grazing sheep and cattle.
Meadows-pastures are those herbaceous formations whose floristic composition is strongly conditioned by the production of forage (obtained by mowing and direct grazing). Quite common in the Park, they’re mainly found near the human settlements and have a thick and homogeneous herbaceous surface made of Graminaceae and Dicotyledons.
The alpine or high-altitude pastures, widespread in the Park, occupy all the areas above the forest line. The floristic composition is variable and conditioned by the nature of the substrate and the altitude.
The snow valleys are depressions in the ground where the snow remains for most of the year, eventually disappearing only for a short time (one to three months at the most). The flora is influenced by the type of substrate (limestone or silica) but is generally made of dwarf willows and Dicotyledons.

WOOD HEDGES

Around the woods, shrubs develop, mainly belonging to three large groups:
1-the willow groves on the banks of the waterways (at low or high altitudes), featuring the dominant presence of different species of shrubby willows.
2-the shrub formations in dry and warm places, mostly made of thorny shrubs such as barberry, raspberry, juniper and brambles.
3-green alder groves, dominated by Alnus viridis, which colonize the slopes of the avalanche gullies, the banks of the alpine streams, and the lower areas of the moraines; there is also some herbaceous vegetation that grows among the alders, mainly consisting of large-leaved and quite tall plants.

Above the woods, the moorlands and some low-altitude wood formations can be found, featuring discontinuous vegetation. There are some small herbaceous plants, lichens and soil mosses; they can be clearly identified in the savin plains (Juniperus sabina). There is also some xerophilous subalpine heath with dwarf juniper, cranberry and bog bilberry; not to mention meso-hygrophilous subalpine heath with rhododendron and bilberry, lingonberry and, once again, bog bilberry. This section of the parks also includes some stretches of windy alpine moorland.

THE WOODS

The woods cover just under 20% of the total surface of the Park and are of great importance, offering shelter to a large number of animal species, as well as protection against the dangers of hydrogeological instability (landslides, avalanches, floods). They are mainly deciduous or coniferous forests.

Broad-leaved woods are made of beeches (Fagus sylvatica), abundant in the section of the park facing Piedmont, but never found in the other one facing Valle d’Aosta. Then there are woods made of sycamore maples (Acer pseudoplatanus) in the gorges, and woods of large-leaved limes (Tilia platyphyllos); those woods are scattered within the park, especially in the most humid areas, on the northern slopes and at lower altitudes.

Chestnut groves (Castanea sativa) can be found as well on in the area facing Piedmont. Those trees grow up to 3.280 ft and are strongly linked to human activities (wood and fruit production). Pioneering and infesting plants can be recognized in relatively recent heterogeneous tree formations: they have developed mainly on the sunny slopes once used for agriculture and livestock feeding. The species mainly found are aspens (Populus tremula), birches, and common hazels (Corylus avellana).

The coniferous woods in the park are made of Scots pine (Pinus sylvestris): they’re much more common in the area facing Valle d’Aosta, on poor, rocky soils exposed to the south.
The Norway spruce forests (Picea abies) are often mixed with larches (Larix decidua) and are probably the most common tree formations in the Park, especially in the middle subalpine level up to 5.905-6.561 ft of altitude.