*1: Newlyn Cliff, 1865, WC (PNZ) (Paton 1969a:
741).
*2: Tregawn, Withiel, 1879, RVT (B) (Paton 1969a:
741).
Habitat notes from C&S are as follows. Mainly
an epiphyte, preferring bark that is nutrient-rich and basic
or circumneutral; very common on Elder; common on Ash, Grey
Willow and Sycamore; fewer records on Alder, Apple, Beech,
Blackthorn, Buddleja, Cortaderia, elms,
Garden Privet, Gorse, Hawthorn, Hazel, Pedunculate Oak, Picea abies (dead
twigs), Salix
caprea, Sessile Oak, Wild Cherry, hybrid poplar. Twice on
decorticated wood of fences. Prefers trees or shrubs in
sheltered or waterside sites and avoids those in very heavy
shade e.g. inside woodland. Frequently on silted bark within
river flood-zones, but usually higher above water-level than
most Orthotrichum
rivulare; also in upper
edge of reservoir inundation zones. Prefers bark of trunks or
branches that are horizontal or inclined to those that are
vertical and often in knot-holes or other irregularities.
Detailed studies of colonisation of an old Elder at Porkellis
Moor showed new twigs first colonised in second year, but that
it doesn't grow large enough to bear capsules until twigs
about six years old; by their tenth year it may be replaced by
pleurocarpous mosses.
Common associates include Amblystegium serpens
var. serpens, Brachythecium
rutabulum, Cololejeunea
minutissima, Cryphaea heteromalla,
Frullania dilatata,
Hypnum andoi, Hypnum cupressiforme
var.
resupinatum, Lejeunea ulicina, Metzgeria
consanguinea,
M. furcata, M. violacea, Orthotrichum
diaphanum, Orthotrichum
pulchellum, Rhynchostegium
confertum, Ulota
bruchii, U. crispa, U. phyllantha, Zygodon conoideus, Zygodon viridissimus
var. viridissimus
and various lichens; scarcer associates include Orthotrichum tenellum,
Radula
complanata.
Occasional records of occurrence (mainly in small
quantity) on rocks or masonry, including concrete (nine
records: fence-posts in sheltered places; bridge parapets,
blocks of masonry debris on ground in woodland, on china clay
spoil and in sheltered quarry, pipe above stream), slaty rock
(one record, shaded on bridge parapet under trees) and granite
(at least ten records: in open and partly shaded by bushes or
trees, on blocks, boulders and grave surrounds). Single
records on top of mortared stone wall, on asbestos-cement of
old shed and on partly shaded boulder probably of
serpentinite.
Commonly c.fr. [only recorded with capsules]:
capsules immature 1-7 (8), 10-12; dehiscing [2 exceptional] (5
few) 6-9 [10, 11]; dehisced [old 1-6],
7-12.