Introduction
The path bends and widens to leave space for the Can Jaume Alzina fountain, in an environment of riverside vegetation at the headwaters of Sobirans’ stream.
The riverside forest we find in this basin is, generally, altered by man, hence the presence of plantations of poplars, bananas and some chestnut trees. There are still fragments of natural riverside forest, especially hazel trees and some ‘verneda’ ridges.
In this place where we are, we can highlight the Hazelnut community of Polystic (Polysticho-Coryletum), dominated by hazelnut (Corylus avellana) and a large fern, the polystic (Polystichum setiferum). In the underbrush, among other species, we also find Corniol (Aquilegia vulgaris L. subsp. Vulgaris), King’s Crown (Chrysanthemum segetum L.) and Barretera or Horse Leg (Petasites pyrenaicus).
We should mention the outcrop of the granite substrate on this stretch of the road. The erosion, mainly because of the water, has created channels to the stone where the runoff accelerates downwards. The action of rainwater accompanied by other types of sediments has eroded, naturally, the granite substrate, here very alterable because of weathering.