The establishment of this Nature Reserve is mainly due to the presence of several specimens of beech trees within the characteristic chestnut tree and oak woodlands: the beech tree is a characteristic species of a mountain environment which found shelter on Collina Torinese during the last glaciations, and therefore is considered a "glacial relict". Different environments characterized by a very rich flora coexist: mountain species alternate with a Mediterranean flora which "migrated" here from the near Ligurian coast during the interglacial periods. Among the rarest species there are the turk's cap-lily, the spurge laurel, and different species of orchids. An important aspect of the Nature Reserve is the forest management, based on criteria of naturalistic forestry; as a matter of fact, the continuous traditional forest cuts (short-turn coppice) would have slowly led to the disappearance of the beech tree. The wildlife of the Nature Reserve is not different from the wildlife of the hills of Piedmont: the mammals include fox, badger, weasel, hedgehog, squirrel; birds include buzzard, goshawk, Tawny owl, little owl, green woodpecker and great-spotted woodpecker, hoopoe, cirl bunting, and several species of passerines. The environment of the hills is characterized by the so-called "Bric", with steep slopes on the side of the Po Plain, including Vaj Woodland, and with gentler slopes on the western side. The presence of soft rocks, not very consistent and easily subject to erosion (sandstone in the lower section and marls in the upper section) causes in the area abundant landslides. Since the 18th century, naturalists have been finding several fossils, finds, and tracks of vegetable and animal organisms living in past epochs and preserved in the rocky strata originating from marine sediments.
Bosco del Vaj, together with Bosc Grand, is also a Special Conservation Area. See the topographic map.