*1: Damp sites of
quarry on down E. of New Grimsby, Tresco, 1959, PDR comm. JAP
(Warburg 1965b: 860, Paton 1969a: 710).
*2: Lane near St Cleer,
1918, RWS (TRU) (Paton 1969a:
710).
A local colonist forming small mainly pure patches
on mainly bare, damp to rather dry, acid substrates that may
be clayey, gritty or stoney and horizontal to steeply sloping.
Once on vertical face of a crumbling granitic boulder.
Commonly unshaded, but also seen partly shaded by Grey Willows
and on steep, N.-facing banks. Found most often in and near
recently abandoned and working parts of china clay quarries
and beside the adjoining tracks and spoil heaps, and on edges
of mica dams, especially on sandy or gritty substrates and
sometimes where flushed with water and on banks and flat areas
of old copper-mine spoil on Bodmin Moor. Associates include Nardia scalaris, Pohlia
annotina.
Sporophytes never recorded in Cornwall.
