First vice-county records of the L. glaucum s. l.:
*1: Madron Moor, 1867,
WC (PNZ) (Paton 1969a: 719).
*2: St Erme, 1861, ES
(TRU) (Paton 1969a: 719).
L.
glaucum and L. juniperoideum were
not usually separated in Britain until the
study by Crundwell (1972); older records are placed as L. glaucum s. l. unless specimens
have been revised subsequently.
Grows in patches that develop into rounded
cushions, sometimes forming large hummocks, but these
infrequently more than 0.5 m across in Cornwall (although up to 0.8 m tall and
0.6 m in diameter at locality east of Temple in
1999). Habitat notes from C&S are as follows. On acidic
humic soil, damp ground-litter, old Molinia caerulea
tussocks and other wet peaty surfaces. Grows mainly on wet
heathland and in acid mires, but also recorded in drier acidic
grassland on Bodmin Moor, on laneside and trackside banks, in
a mature Beech wood, and on a slope in open Sessile Oak
woodland from where it extended onto vertical soil on low
cliff only 1.5 m above HWST level of a sheltered estuarine
creek. One record of small cushions on soil on top of very old
ruined walls (Chysauster). Usually unshaded, but also partly
shaded in open woodland. Associates include Leucobryum
juniperoideum (in woods), Polytrichum strictum
(growing on Leucobryum hummock),
Campylopus
flexuosus, Calluna
vulgaris, Erica
spp., Pteridium
aquilinum. Various small liverworts grow in or over its
hummocks in mires, especially when they are poorly grown or
moribund (including Kurzia pauciflora, Odontoschisma
sphagni). Its hummocks are often occupied by ant
nests.
Not seen c.fr. (Paton 1969 gives 'rarely' c.fr. in
Cornwall). See Blackstock (1987) for notes on ecology and
sexual reproduction.