The realm of beech, fir and larch
Broadleaf and conifer woods are the two formations present in the Park territory.
There are many reasons for this situation. First of all, it is worth mentioning the influence of the Mediterranean climate in this part of the Alps, which is less than 40 kilometres as the crow flies. Its influence gives it a typically oceanic, temperate and humid character, both favourable to beech and adverse to conifers, which, with the exception of the silver fir, prefer more clearly continental climates. Secondly, it is worth remembering the role played by the typically rugged geomorphology of the protected area: full of narrow valleys with steep slopes and mountains of compact crystalline rock, it is generally more easily colonized by broad-leaved trees. Last but not least, a selective advantage for the beech tree was human activity**. Indiscriminate use of the wood resources in the forests has unintentionally favoured beech forests, which are better able to withstand cutting than conifers, thanks to their marked suckering capacity.
Spreading from 1,000 metres to 1,700-1800 metres above sea level, the maximum altitude for the Alps, the beech forest is mostly a dense group of bushy trees of the same age. This aspect of the beech forest is related to the way people have managed the woods. Coppicing exploits the characteristic capacity of broadleaved trees to emit suckers from their stumps, which is responsible for the renewal of the forest.
These coppices still suffer today from the intense exploitation of the past, which involved cuts at very close intervals of eight to ten years. It goes without saying that these coppices have no great naturalistic or landscape value. The undergrowth, in fact, is very poor due to the dense shade and the presence of thick litter. It is enriched by small herbaceous species, such as the Hepatica nobilis, decorating the uniform soil with its delicate purple blooms. It flowers before the beeches are in leaf, compensating for the low sunlight of these woods with its early start.
In the Park there are some isolated examples of beech forests managed as mature stands, i.e. woods where renewal is by seed. The most famous forest is the Bosco Bandito di Palanfrè. Situated above Palanfrè a small village in the Val Grande at the eastern end of the protected area. The houses are in a position where they would be exposed to avalanches. For this reason, since the early 18th century, but probably even before, cutting in the beech wood above the village was forbidden ("banned"). Documents kept in the municipal archives of Vernante, dated 1741, are the first written evidence of the wood's state of protection. The upper boundary of the beech forest, which only covers an area of 9 hectares, coincides with the upper altitude limit for the species. The small forest that grew up around the hunting lodges of San Giacomo di Entracque, where you can admire some centuries-old trees, also had the function of sheltering the buildings from avalanches. Here you can see the influence of a gardener, who softened the already elegant posture of the beech trees to create a landscape around the summer residences of the royal family worthy of their visitors.
Coniferous forestsThere are four species of conifers in the Park: silver fir, spruce, larch and stone pine. Among these, the silver fir is the most suitable species for the sub-oceanic climate that characterizes this part of the Alps. However, it is far from reaching the spread of the other typically mesophilous species, the beech, with which it creates mixed forest consortia, due to intense felling in the past and the unfavourable conformation of the territory. The most beautiful specimens are those that make up the large forest near the Terme di Valdieri, located at the entrance to the Valletta and Valasco valleys.
Spruce, larch and stone pine are species linked to a more continental type of climate, characterized by hot, dry summers and cold, dry winters. In this region with a temperate and rainy climate, they manage to thrive by settling in the innermost areas of the valleys or in the shelter of large mountain massifs, where the most favourable conditions are created. The three species can intermingle to form mixed forests.
Larch and stone pine show marked pioneer aptitudes. The larch, a sun-loving forest species, colonizes the edges of gullies and slopes covered with stones and scree. In the Park it goes up to 2500 metres, an altitude limit considered the highest in the whole of Europe. A beautiful example of pioneer larch wood is offered by the right side of the Meris Valley, a rocky environment with a steep slope regularly beaten by avalanches.
The Swiss stone pine is the conifer able to reach the highest altitudes: isolated specimens, with a twisted and distressed appearance, reach an altitude of 2800 metres on crests and cliffs. The rocks of Mount Frisson, at the head of the Vallone degli Alberghi, and the adjacent walls of Rocca dell'Abisso, form the eastern limit of its range .