Lichen  (Bacidia incompta)

This lichen was formerly widespread in Britain, reaching as far north as Aberdeenshire, and was once particularly common in the south-east of England, but rare in more oceanic areas (5). However, it has suffered a severe decline, and has been completely lost from many of its former sites (5). It persists in the New Forest, and a few sites in Dorset, Devon and Cornwall (7), one site in Wales, and in some areas of Scotland (2). Outside of Britain, this species occurs in continental Europe, North America and Madeira (2).

Grows on the trunks of mature trees, mainly on elm in Britain, although it may also occur less commonly on ash, holly, beech, sycamore and hornbeam (2). It often grows in rain-seepage tracks on the bark, which are rich in nutrients, or underneath wounds in the bark (2). Main habitats supporting this species are old parkland and wayside trees in open conditions (2).