Montane, mossy Pinus sylvestris forests of the Pyrenees; characteristic of regions with a moderately dry, sunny climate, they occur, at all exposures but mostly on ubacs, in a wide belt on the south flank of the range, with limited outposts on the north flank. Characteristic is the abundance of wintergreens (Pyrola chlorantha, P. minor, Moneses uniflora, Orthilia secunda) and of mosses (Hylocomium splendens, Rhytidiadelphus triquetrus, Pleurozium schreberi); Vaccinium myrtillus, Luzula nivea, Hepatica nobilis are usually present.
Calcicolous formations of Pinus sylvestris with Sorbus aria, Amelanchier ovalis, Ribes alpinum, Prunus mahaleb, Cotoneaster integerrimus, Polygala calcarea, Helleborus foetidus, Valeriana montana, Festuca gautieri.