The chestnut is one of the most common trees in the valley. In many areas, it has been introduced at the expense of the “natural” vegetation, because of its value as a source of nuts, timber and bedding for livestock. Many animals live in chestnut woods, using the crevices in dead trunks for protection and the fruit, sweet chestnuts, as food.
The sweet chestnut was probably brought to Valtellina by the ancient Romans; it spread because of the value of its fruit. The cultivation of chestnuts remained important even after the introduction of other crops such as wheat, rye, maize and, much more recently, potatoes. Many attempts were made to create stands of these trees, even in unfavourable areas; dry-stone walls were built in the 16th and 17th centuries as part of an effort to improve access to chestnut woods and stop the nuts from rolling down the slopes.
Sweet chestnut trees usually have a grafting scar on the trunk, at a variable height. Grafting is a technique which allows the transplantation of a branch of a tree with favourable foliage and fruit characteristics onto another tree known to have a robust root system. Thus a tree is obtained which combines both these features and is stronger than either of the single “component” trees. In the case of the chestnut, the graft is made principally to obtain larger fruit.
A herbivorous butterfly often to found in woods of broad-leaved trees in July and August; in certain climatic and ecological conditions its larvae may cause serious damage to vegetation.
A predaceous insect that lives on trunks and in treetops, where it hunts mainly the larvae of several butterflies; during the summer it prepares to pass the winter underground.
A nocturnal bird of prey which eats small mammals and builds its nest in holes in large trees.
A climbing diurnal bird with a chisel-like beak with which it captures the larvae of insects that infest tree trunks. It nests in holes in trees which it makes itself.
A diurnal rodent that builds a spherical nest in trees, usually where branches fork near the trunk. It eats seeds, shoots, tubers and mushrooms and does not hibernate.
An insectivore which is active both during the day and at night, and builds its nest in the base of a tree trunk.
These ants build nests under stones or in the earth, protected with plant debris.
A nocturnal bat that eats mainly insects caught and devoured in flight, identified by means of echolocation. During the day, it hides in dark cavities (caves or hollow logs).
A nocturnal rodent which eats mainly dry fruits and seeds. It builds a summer nest high up in trees and a low winter nest in a hollow log or underground.
An insect that lives in colonies in which the eggs are laid by a queen. An important producer of honey, made from flower nectar and pollen. Sweet chestnut flowers are actively sought after by the bees, which produce a dark and intensely aromatic honey from them.
An omnivorous nocturnal mammal that eats mainly earthworms, but also small mammals and sometimes bulbs, hazelnuts and acorns. It lives in a sett (burrow) dug into the ground.