 The habitats protected by Pillar and Ennerdale Fells SSSI include natural woodland such as Side Wood, an example of old sessile oak woods.The trees of Ennerdale are important as an example of altitudinal succession (from "native upland birch-oak woodland at 120 m on the shores of Ennerdale (Water) the vegetation changes through sub-montane heaths and grasslands to montane heaths along the summit ridge at an altitude of 890 m").The condition of the SSSI´s habitats has been assessed as "Unfavourable - Recovering".