liverworts mosses

Key features for identifying
liverworts
Key features for identifying
Mosses
Growth form. There are two sorts of liverworts; leafy
liverworts have a stem and leaves and resemble a
moss, whereas thallose or thalloid liverworts have a
simple strap of tissue with no stem or leaves. Leafy
liverworts can form erect cushions and turfs while some
are creeping and closely apressed to rock or tree. The
size of the plant is also important; a number of oceanic
liverworts are very, very small.
Leaf shape. This is all-important in leafy liverworts and
is much more variable than in mosses. Liverwort leaves
can be simple and round, they can be deeply divided
into filaments or into broader lobes, the lobes can be
of different sizes and can be bent over or under each
other and formed into flaps or pouches. Many liverworts
also have pronounced teeth on the margin of the leaf,
visible without a hand lens. Many leafy liverworts also
have under-leaves, usually much smaller than the main
leaves, and on the lower side of the stem.
Growth form. Leaving aside the very distinctive bogmosses (Sphagnum), mosses can be split into two
groups, acrocarpous and pleurocarpous. There is a
technical difference between these two forms but in
practical terms, acrocarps usually have erect stems
and grow in cushions or turfs while pleurocarps tend
to grow with main stems parallel to the ground (or rock
or tree trunk) and form wefts. The often dense growth
form of acrocarps means that their sparse branches
are obscured while in pleurocarps the branches are
usually many and easily seen.
Photoset Left - A variety of leafy liverwort leaves, clockwise
from top left: Taylor’s Flapwort (Mylia taylori), Prickly
Featherwort (Plagiochila spinulosa), Ciliated Fringewort
(Ptilidium ciliare), White earwort (Diplophyllum albicans note upper lobe bent over the top of the lower and the line
of longer cells), Common Paw-wort (Barbilophozia floerkei),
Bifid Crestwort (Lophocolea bidentata), Creeping Fingerwort
(Lepidozia reptans), part of stem with ‘fingered’ leaves.
Above - Left: acrocarpous Scott’s Fork moss (Dicranum
scottianum) ; right: pleurocarpous Larger Mouse-tail
Moss (Isothecium alopecuroides).
Above - Irregular branching in Red-stemmed Feathermoss (Pleurozium schreberi) on the left and regular
tri-pinnate branching in Glittering Wood-moss
(Hylocomium splendens) on the right; note the red stems.
Abbreviations
Leaf shape. Moss leaves have a variety of shapes but
they tend to be variations on the same theme, with
a relatively broad base tapering to a narrower apex.
Some leaves are long and narrow and taper to a fine
point, others have a broad triangular shape tapering
shortly to a sharp point. Other mosses have leaves
with a blunt apex and a few species have round leaves.
Another useful character is whether or not the leaves
are all curved in the same direction (falcate) or bent
back from the stem (reflexed or squarrose). Some
leaves also have teeth on the margin, usually visible
only with a hand lens.
NR – nationally rare; NS – nationally scarce; BAP – a Biodiversity Action Plan species;
S8 – listed on Schedule 8 of the Wildlife and Countryside Act (1981).
Further information
Books
British Mosses and liverworts: a field guide. British Bryological Society (2010). The first comprehensive colour field guide to
bryophytes with good keys and hundreds of photos.
Mosses and Liverworts; Gordon Rothero (2005). A brief, general introduction to Scottish bryophytes, part of the ‘Naturally
Scottish’ series published by Scottish Natural Heritage, Battleby.
Bryophytes of native woods – a field guide to common mosses and liverworts of Scotland’s native woods. Carol L Crawford
(2002), Native Woodlands Discussion Group. A small booklet with good colour photos.
Mosses and Liverworts. New Naturalist 97, Porley RD & Hodgetts NG, (2005). Collins. An accessible account of our bryophyte
heritage with a good section on woodlands.
The geographical relationships of British and Irish bryophytes; Hill MO & Preston CD (1998). Journal of Bryology, 20: 127-226.
Information and advice
www.britishbryologicalsociety.org.uk. The British Bryological Society has an excellent website with useful information on
publications, courses, field meetings and lots of pictures.
www.nwdg.org.uk. The Native Woodland Discussion Group runs courses on Atlantic mosses and liverworts.
Advice and Support
Plantlife Scotland can help you in your quest for information and support.
Plantlife Scotland, Balallan House, Allan Park, Stirling, FK8 2QG
Tel: +44 (0) 1786 478509 www.plantlife.org.uk [email protected]
© March 2010 ISBN 978-1-907141-24-9
Plantlife Scotland is part of Plantlife International – the Wild Plant Conservation charity, a charitable company limited by guarantee. Registered in
Scotland (SC038951) and in England and Wales (1059559). Registered company no 3166339.
This guide has been written and illustrated for Plantlife Scotland by Gordon Rothero.
All photos © Gordon Rothero unless otherwise stated. Cover photo © Laurie Campbell.
Photoset above - A variety of moss-leaf shapes, clockwise
from top left: Dotted Thyme-moss (Rhizomnium
punctatum), Catherine’s Moss (Atrichum undulatum),
Little Shaggy-moss (Rhytidiadelphus loreus), Yellow
Fringe-moss (Racomitrium aciculare), Common Striated
Feather-moss (Eurhynchium striatum), Cypress-leaved
Plait-moss (Hypnum cupressiforme).
Leafy liverwort; size: small to medium-sized forming tight
patches of erect stems; colour: mid or yellow green, often with
some shoot tips red with gemmae; leaves: rounded-rectangular
in outline but with three or four lobes, each lobe usually ending
in a little sharp point (lens); underleaves: usually visible with
a lens, with two long pointed lobes; habitat: on thin peaty soil
on rocks and in scree; note: a very similar and equally common
species, Common Paw-wort (Barbilophozia floerkei), never has
gemmae and lacks points on the lobes
Leafy liverwort NS; size: very small and forming thin patches
of upright stems; colour: yellow or yellow green with shoot
tips red with gemmae; leaves: tiny with two lobes but hardly
visible even with a lens; habitat: on well-rotted, rather damp
logs; note: not easy to see without putting your nose to the
log but once spotted easily recognised by the erect stems
with red tips.
Branching. For some of the pleurocarps it is useful
to note what the pattern of branching looks like. Is
it regular with branches more or less opposite each
other on the main stem (pinnate) or irregular? Are
the regular branches branched again (bi-pinnate) and
again (tri-pinnate) giving a fern-like structure?
Colour. Colour and texture are all-important field
characters. Many species have a particular shade,
admittedly usually of green, which coupled with
the structure of stem and leaf, gives a texture which
is what the eye picks up from a distance. Another
important colour is that of the main stem; when
the leaves are dry they become opaque and it may
be necessary to scrape away some leaves with your
fingernail to see the stem colour.
Hatcher’s Paw-wort (Barbilophozia hatcheri)
Michael Lüth
Heller’s Notchwort (Anastrophyllum hellerianum)
Horned Flap-wort (Lophozia longidens)
Michael Lüth
Above - Left: a thallose liverwort, Overleaf Pellia (Pellia
epiphylla) with fruits; right: a leafy liverwort with round
leaves, Autumn Flapwort (Jamesoniella autumnalis).
MOSSES
Monster Paw-wort (Tetralophozia setiformis)
Michael Lüth
LIVERWORTS
LIVERWORTS
Leafy liverwort NS; size: small and forming loose patches
of normally procumbent stems; colour: mid or dark green
with some shoot tips red with gemmae; leaves: rectangular
in outline but with two pointed lobes with an acute gap
between them, the leaves near the stem apex having dark red
gemmae (lens); habitat: often present on the older, sprawling
stems of juniper and also on thin peaty soil on rocks; note:
the red gemmae and the relatively long sharp lobes are
characteristic.
Curled Notchwort (Anastrophyllum saxicola)
Leafy liverwort NS; size: small to medium sized but often
forming large dense cushions of erect stems; colour: yellow
or sometimes orange or dark brown; leaves: inserted close
together across the stem with up to four long pointed lobes with
a narrow gap in between, lobes erect and pointing up the stem;
underleaves: large and with two lobes; habitat: on thin peaty
soil on rocks and in scree; note: a characteristic species of dry
scree in eastern hills and readily recognised by the tight cushions
of erect stems and narrow lobes on the closely-set leaves.
Ciliated Fringewort (Ptilidium ciliare)
Nerve (or costa). A very useful character is whether
the moss leaf has a nerve or not. The nerve (or costa)
is a thickened rib of tissue running up the centre of
the leaf which looks like a dark line if the leaf is held
against the light and viewed with the hand-lens. It
usually extends beyond halfway up the leaf and may
reach the apex.
Moss or liverwort?
Initially this is a tricky question but with a little experience it ceases to be a problem. Thallose liverworts are
easy but leafy liverworts can be passed over as mosses by the uninitiated. In most mosses the leaves grow all
around the stem but in most liverworts the main leaves are in two ranks down each side of the stem, sometimes
with a line of smaller under-leaves below. Most moss leaves are roughly triangular, wide at the base and narrow
to the apex; few liverworts are like that. Moss leaves never have lobes whereas many leafy liverworts do. Most
mosses with round leaves have a nerve; no leafy liverworts have a nerve but a few have lines of cells running up
the centre of the leaf.
Leafy liverwort NR; size: medium sized but often forming
large dense cushions of erect stems; colour: yellow or
greenish brown, occasionally with a reddish tinge; leaves:
complex, two lobed with the smaller upper lobe folded up over
the larger lower lobe, the lower lobe is concave and the top
edge of the upper lobe is turned in towards the stem; habitat:
on thin peaty soil on rocks and in scree; note: a rare species
of scree, the dense patches of erect stems with closely set,
bilobed leaves are usually easily identified.
Leafy liverwort; size: medium-sized but often forming large
cushions or patches; branching: irregularly pinnate, occasionally bipinnate, at right-angles to the stem, the branches blunt at the end
colour: usually some shade of yellow but may be variegated red,
green or brownish; leaves: two lobes but the most noticeable feature
is the margin which has lots of long narrow teeth (cilia) easily visible
with a lens; underleaves: similar in shape to the main leaves but
much smaller; habitat: on well-drained sites with other bryophytes
amongst ericaceous shrubs, in heathy grassland and in woodland;
note: confusion only possible with the related but much smaller
Tree Fringewort (Ptilidium pulcherimum) and Wood’s Whipwort
(Mastigophora woodsii) a scarce western oceanic species of humid
sites which has longer branches tapering to a point.
Bryophytes of
Scotland’s pine woodlands
British Lichen Society
MOSSES
Introduction
This Plantlife field guide will help those who want to
go a little further in identifying the carpets of mosses
and liverworts that are such an obvious feature of
many of our Scots pine woodlands. This guide deals
with some of the typical species and a few of the more
uncommon and rare species of particular habitats
within the woodland. It is focused largely on the
woodlands of the east of Scotland, so, for the pine
woods of the west, particularly Beinn Eighe, the guides
for Atlantic woodland would be more useful.
What are pine woodlands?
They are semi-natural stands of woodland where Scots
pine forms a significant proportion of the canopy.
Within these woodlands pine or birch may be the
dominant tree and there will also be rowan, aspen
and more locally alder and willows, especially along
water-courses. Some woodlands, mostly in the east
of Scotland, have a patchy understory of juniper and
occasionally of hazel.
What are mosses and liverworts?
Mosses and liverworts (collectively known as
bryophytes) are two of the oldest groups of land plants
and have had millions of years to evolve a variety of
species that have colonised almost all habitats apart
from the sea. Most have a simple structure with a
main stem and more or less frequent branches covered
in leaves. They do not have roots but absorb water and
minerals directly into the (usually) single layer of cells
in the leaves. Though some bryophytes are strongly
coloured, often red or purple, most are some shade
of green and an appreciation of the many shades of
green is a useful quality in anyone wishing to identify
these small plants.
Why are the mosses and liverworts important?
Bryophytes in woodland are an excellent indicator
of habitat quality and contribute much to the
functioning of the woodland ecosystem, as well as
giving character and aesthetic appeal. The UK has
some 1100 species of bryophyte, approximately 65%
of the European flora; in comparison our vascular
plants total only 15%. Our remnants of Atlantic
woodland have as great a diversity of bryophytes as
almost anywhere else on the planet. Our pinewoods
are less diverse but have a more continental flora and
affinities with the forests of Scandinavia and include a
number of Biodiversity Action Plan (BAP) species that
are rare or absent elsewhere in the UK.
Bryophyte communities
A number of the plants illustrated in this guide are
very precise as to the habitat they need but it is
possible to group species into broad communities
within the pinewoods. It needs to be emphasised that
there will be an overlap as large woodland floor species
can cover rocks and the species on rocks and the bases
of trees are often the same.
Woodland floor: on the soil of the woodland floor,
species have to compete with flowering plants and
with the accumulation of leaf litter and so the mosses
here tend to be large and relatively fast-growing.
Where the woodland is heathy, as is common
under pine and birch, the dominant bryophytes are
large pleurocarpous species like Glittering Woodmoss (Hylocomium splendens), Big Shaggy-moss
(Rhytidiadelphus triquetrus), Red-stemmed Feathermoss (Pleurozium schreberi), Heath Plait-moss
(Hypnum jutlandicum), Ostrich-plume Feather-moss
(Ptilium crista-castrensis) and, in more humid woods,
Red Bog-moss (Sphagnum capillifolium), Little
Shaggy-moss (Rhytidiadelphus loreus) and Waved
Silk-moss (Plagiothecium undulatum). These species
are often abundant and occur to the exclusion of all
else. In drier woodland with a more complete pine
canopy, the floor may be more open with areas of bare
pine needles; here there are often dense cushions of
Broom Fork-moss (Dicranum scoparium) and Dusky
Fork-moss (Dicranum fuscescens) running up onto the
tree bases.
Rocks, crags and scree: Within pine woodland there
are often areas of crag and scree which have some
characteristic species. Grey carpets of Woolly Fringemoss (Racomitrium lanuginosum) are common and
cushions of Dusky Fork-moss (Dicranum fuscescens)
are frequent and there may be patches of the liverwort
Hatcher’s Paw-wort (Barbilophozia hatcheri). Two
characteristic species of scree are the liverworts
Monster Paw-wort (Tetralophozia setiformis) which
is quite common here and the rare Curled Notchwort
(Anastrophyllum saxicola).
Trees and logs: Bryophytes do not like pine bark and
are usually limited to the base of the tree. The flora on
birch is also poor but where there are hazels or aspens
the flora can be quite rich, particularly with species
of Bristle-mosses (Orthotrichum). Dead wood can
often provide a humid habitat and has an interesting
flora; in damp places species like Wood-rust (Nowellia
curvifolia) and Palmate Germanderwort (Riccardia
palmata) are common and good logs may have the
tiny liverwort Heller’s Notchwort (Anastrophyllum
hellerianum) and the rare moss Green Shield-moss
(Buxbaumia viridis).
‘Bryologising’
Although identifying species initially needs a
modicum of determination, it is possible to quite
quickly become familiar with the common mosses and
liverworts in pine woodlands. They have the virtue of
being available all the year round and grow in really
nice places. Though some of the species are very
distinct, even from some metres away, the process
and the enjoyment will be enhanced if you get used
to using a hand-lens (at least x10) to reveal the finer
features on which identification sometimes depends.
In the descriptions, where a lens is necessary, it is
indicated by (lens); remember, hand-lens to the eye
and move the plant into focus.
In these guides, English names have been used
alongside the Latin; these are not ‘common names’
in the same sense as those for flowers because they
are all recent inventions and as yet are hardly used
except in publications like this! Latin names should
always be used for recording purposes to avoid any
ambiguity.
Green Shield-moss (Buxbaumia viridis)
Broom Fork-moss (Dicranum scoparium)
Dusky Fork-moss (Dicranum fuscescens)
Rusty Fork-moss (Dicranum spurium)
Wavy Fork-moss (Dicranum undulatum)
Glittering Wood-moss
Heath Plait-moss (Hypnum jutlandicum)
(Hylocomium splendens)
NR, BAP, S8; fruit: The leaves of this strange moss
are too tiny to see and it is only the large capsule
that attracts attention, resembling a ‘bug-on-astick’. This capsule is 5mm or so long on a stem of
about the same length and held erect when young
and at more of an angle when mature. Bright green
in the winter, brown and peeling when mature in
the summer; habitat: most sites are on rotting logs
or stumps but it has been found on old wood-ant
nests and rarely on bark of living trees; note: a
Schedule 8 species so should not be disturbed.
Waved Silk-moss
(Plagiothecium undulatum)
Pleurocarpous; size: robust and usually forming
large patches; branching: sparse and irregular;
colour: typically a whitish green; stem: green;
leaves: rounded-triangular, tapering shortly to
a point and with distinct undulations running
across the leaf, no nerve; habitat: woodland floor,
ledges, boulder tops; note: the whitish-green colour
resembling ‘white worms’ and the undulate leaves
make this an easy moss to recognise.
Acrocarpous; size: medium-sized and usually
forming cushions and occasionally tight turfs;
branching: obscured; colour: mid-green, leaves:
long, very narrowly triangular with a toothed apex;
leaves often curved in one direction; habitat: on
drier open parts of the woodland floor, often on pine
litter in bare areas and often around the base of pine
trees, but also on rocks and logs; note: the much
larger Greater Fork-moss (Dicranum majus) is also
common in more humid woodland, it has very long,
regularly curved leaves.
Red-stemmed Feather-moss
(Pleurozium schreberi)
Pleurocarpous; size: robust and usually forming
large patches; branching: irregular and rather
untidy; colour: mid to yellow-green and ‘chaffy’
when dry; stem: red; leaves: rather roundedtriangular, tapering to a blunt point, no nerve;
habitat: woodland floor, ledges, boulder tops
Acrocarpous; size: medium-sized and usually
forming cushions and occasionally tight turfs;
branching: obscured; colour: mid-to dark green,
leaves: long, very narrowly triangular with a
fine, toothed apex (lens), leaves often curved in
one direction; habitat: on drier open parts of the
woodland floor, often on pine litter in bare areas
and often around the base of pine trees, but also
on rocks and logs; note: easily confused with
Broom Fork-moss (Dicranum scoparium) but the
fine, wispy apex is distinctive, particularly when
dry.
Common Haircap (Polytrichum commune)
Bristly Haircap (Polytrichum piliferum)
Acrocarpous; size: very large and forming large
hummocks or lawns; branching: sparse and
obscure; colour: dark green; leaves: a white base
that clasps the stem, above narrowly triangular to
a shortly pointed apex and strongly toothed; the
leaves are opaque and look thick because of the
numerous lamellae on the upper surface; habitat:
in damper areas and boggy ground; note: the
largest of several similar species in the woodlands;
also illustrated is Bristly Haircap (Polytrichum
piliferum) a much smaller plant with a white hair
point which grows in drier places like rock tops
(N.B. the pictures are not to scale).
Acrocarpous NS, BAP; Size: medium-sized and
forming open turfs or just scattered stems; branching:
obscured; colour: yellow to mid-green, leaves:
tapering abruptly from a broad base to a fine apex,
irregularly undulate and concave giving the shoots a
fat appearance; habitat: most frequent on thin peat
under open, ‘leggy’ heather on moderate to steep
slopes but also occurring in damper heath; note: a
very different ‘habit’ from other Dicranum species and
might be overlooked as the common moss Swans-neck
Thyme-moss (Mnium hornum) when dry.
Ostrich-plume Feather-moss
(Ptilium crista-castrensis)
Pleurocarpous; size: robust and often forming
large patches; branching: very closely pinnate and
so feather-like hence the English name; colour:
mid to yellow-green; stem: green and furry with
green filaments under the lens; leaves: narrowly
triangular, tapering to a long fine point, no nerve,
all strongly curved in one direction; habitat:
woodland floor, ledges, boulder tops; note: a
beautiful and easily recognisable moss and very
characteristic of pinewoods.
Acrocarpous NS, BAP; size: medium to robust
and forming dense cushions which can be large;
branching: obscured; colour: yellow to olive-green,
leaves: long, narrowly triangular with a rather short,
toothed apex, regularly and strongly undulate;
habitat: in boggy areas within the woodland where
there has been little disturbance; note: the olive-green
colour and the habit and habitat are useful characters
but this is a difficult plant to spot despite its size.
Big Shaggy-moss
(Rhytidiadelphus triquetrus)
Pleurocarpous; size: very robust and often
forming large patches; branching: irregular
and rather untidy; colour: yellow-green, strawcoloured when dry; stem: red but often obscured
by the leaves; leaves: triangular, pale yellow-green
and again rather untidy; habitat: woodland floor,
ledges, boulder tops; note: easily recognised by
the large, erect stems and untidy, ‘chaffy’ leaves.
Pleurocarpous; size: robust and usually forming
large patches; branching: regular with branches
branched again, like a small fern; colour: mid to
yellow-green, often ‘chaffy’ when dry; stem: red,
springy; new growth emerging from old frond and
may form several layers of fronds, hence ‘stepstair moss’; leaves: broadly triangular, no nerve;
habitat: woodland floor, ledges, boulder tops.
Little Shaggy-moss
Pleurocarpous; size: small and forming untidy
patches or straggling stems; branching: irregularly
pinnate with all the branches in the same plane
so the shoots look flat; colour: pale-green, often
whitish when dry; stem: green; leaves: narrow,
rounded-triangular, no nerve and with a fine
pointed tip which is turned down giving the
shoots a ‘plaited’ appearance; habitat: a common
species amongst the heather and blaeberry in
heathy woodland; note: Cypress-leaved Plait-moss
(Hypnum cupressiforme), a very common species
in a variety of habitats, is similar but is usually
greener and has less regular branching.
Red Bog-moss (Sphagnum capillifolium)
(Rhytidiadelphus loreus)
Pleurocarpous; size: robust and usually forming
large patches; branching: irregular; colour: mid to
yellow-green; stem: red, springy; leaves: broadly
triangular, no nerve; curved in one direction
so that the stem ends look hooked; habitat:
woodland floor, ledges, boulder tops; note: a bit
smaller, neater and greener than Big Shaggy-moss
(Rhytidiadelphus triquetrus), with hooked shoottips, and usually in more humid sites, so more
frequent in the western woods.
Bog-moss; size: medium sized and forming
swelling cushions or hummocks of erect
stems and often as a loose turf under heather;
branching: a bunch of tight branches at the top
of the stem (capitulum) and whorls of branches
below; colour: often red or pink but variegated
green in more shaded sites; leaves: branch leaves
are narrowly triangular ; habitat: an abundant
and locally dominant plant in more humid
woodland, in valleys or on N-facing slopes note:
other species of Bog-moss may occur in the
woodland but this is the most frequent species.
LIVERWORTS
Above - Left: a thallose liverwort, Overleaf Pellia (Pellia
epiphylla) with fruits; right: a leafy liverwort with round
leaves, Autumn Flapwort (Jamesoniella autumnalis).
MOSSES
MOSSES
Key features for identifying
liverworts
Key features for identifying
Mosses
Growth form. There are two sorts of liverworts; leafy
liverworts have a stem and leaves and resemble a
moss, whereas thallose or thalloid liverworts have a
simple strap of tissue with no stem or leaves. Leafy
liverworts can form erect cushions and turfs while some
are creeping and closely apressed to rock or tree. The
size of the plant is also important; a number of oceanic
liverworts are very, very small.
Leaf shape. This is all-important in leafy liverworts and
is much more variable than in mosses. Liverwort leaves
can be simple and round, they can be deeply divided
into filaments or into broader lobes, the lobes can be
of different sizes and can be bent over or under each
other and formed into flaps or pouches. Many liverworts
also have pronounced teeth on the margin of the leaf,
visible without a hand lens. Many leafy liverworts also
have under-leaves, usually much smaller than the main
leaves, and on the lower side of the stem.
Growth form. Leaving aside the very distinctive bogmosses (Sphagnum), mosses can be split into two
groups, acrocarpous and pleurocarpous. There is a
technical difference between these two forms but in
practical terms, acrocarps usually have erect stems
and grow in cushions or turfs while pleurocarps tend
to grow with main stems parallel to the ground (or rock
or tree trunk) and form wefts. The often dense growth
form of acrocarps means that their sparse branches
are obscured while in pleurocarps the branches are
usually many and easily seen.
Photoset Left - A variety of leafy liverwort leaves, clockwise
from top left: Taylor’s Flapwort (Mylia taylori), Prickly
Featherwort (Plagiochila spinulosa), Ciliated Fringewort
(Ptilidium ciliare), White earwort (Diplophyllum albicans note upper lobe bent over the top of the lower and the line
of longer cells), Common Paw-wort (Barbilophozia floerkei),
Bifid Crestwort (Lophocolea bidentata), Creeping Fingerwort
(Lepidozia reptans), part of stem with ‘fingered’ leaves.
Above - Left: acrocarpous Scott’s Fork moss (Dicranum
scottianum) ; right: pleurocarpous Larger Mouse-tail
Moss (Isothecium alopecuroides).
Branching. For some of the pleurocarps it is useful
to note what the pattern of branching looks like. Is
it regular with branches more or less opposite each
other on the main stem (pinnate) or irregular? Are
the regular branches branched again (bi-pinnate) and
again (tri-pinnate) giving a fern-like structure?
Above - Irregular branching in Red-stemmed Feathermoss (Pleurozium schreberi) on the left and regular
tri-pinnate branching in Glittering Wood-moss
(Hylocomium splendens) on the right; note the red stems.
Abbreviations
Further information
Books
Information and advice
www.britishbryologicalsociety.org.uk. The British Bryological Society has an excellent
website with useful information on publications, courses, field meetings and lots of pictures.
www.nwdg.org.uk. The Native Woodland Discussion Group runs courses on Atlantic mosses and liverworts.
Advice and Support
Plantlife Scotland can help you in your quest for information and support.
Plantlife Scotland, Balallan House, Allan Park, Stirling, FK8 2QG
Tel: +44 (0) 1786 478509 www.plantlife.org.uk [email protected]
© March 2010 ISBN 978-1-907141-23-2
Plantlife Scotland is part of Plantlife International – the Wild Plant Conservation charity, a charitable company limited by guarantee.
Registered in Scotland (SC038951) and in England and Wales (1059559). Registered company no 3166339.
This guide has been written and illustrated for Plantlife Scotland by Gordon Rothero
All photos © Gordon Rothero, unless otherwise stated. Cover photo © Laurie Campbell.
Woolly Fringe-moss (Racomitrium lanuginosum)
Oceanic, NS. Acrocarpous moss; size: large and usually
forming loose cushions within the heath; branching:
obscured; colour: usually a shiny, dark green; stem: often
reddish; leaves: very narrowly triangular, tapering to a very
long, fine point which is formed mostly from the broad
nerve; habitat: in lower stands of the heath, especially
where rocky or below crags; note: two very similar species
Beaked Bow-moss (Dicranodontium denudatum) and
Orange Bow-moss (Dicranodontium asperulum) also occur
in oceanic heath.
Acrocarpous moss; size: large and usually forming
sprawling patches; branching: unlike most acrocarpous
mosses, there are frequent irregular branches; colour:
usually grey when dry and blackish-green when wet;
stem: green; leaves: narrowly triangular, tapering to a long,
toothed white ‘hair-point’; habitat: an abundant and locally
dominant plant in hilly areas, on rocks and in mire and
heath; note: an important and unmistakeable component
of our upland vegetation and a constant in oceanic heath.
Red Bog-moss (Sphagnum capillifolium)
Skye Bog-moss (Sphagnum skyense)
Bog-moss; size: medium sized and forming swelling
cushions or hummocks of erect stems but in the oceanic
heath usually as a loose turf under the heather; branching:
a bunch of tight branches at the top of the stem (capitulum)
and whorls of branches at intervals below; colour: often
red but in the oceanic heath more frequently green with
varying amounts of red; leaves: branch leaves are narrowly
triangular; habitat: an abundant and locally dominant
plant in hilly areas in both mire and heath; note: other
species of Sphagnum occur in this community but this is
the most frequent species.
Oceanic, NR. Bog-moss; size: large, twice the size of
Red Bog-moss (Sphagnum capillifolium), and forming
loose patches in the turf; branching: a bunch of long
branches at the top of the stem (capitulum) giving an
untidy appearance and whorls of long branches below;
colour: often red or pink but with some variegated green ;
leaves: branch leaves are narrowly triangular ; habitat: in
grassy heath and often associated with Juniper Prongwort
(Herbertus aduncus ssp. hutchinsiae), and Carrington’s
Featherwort (Plagiochila carringtonii); note: the size,
colour, long branches and habitat are useful characters;
outside of the west of Scotland only known from one site in
Wales and one in Ireland.
Leaf shape. Moss leaves have a variety of shapes but
they tend to be variations on the same theme, with
a relatively broad base tapering to a narrower apex.
Some leaves are long and narrow and taper to a fine
point, others have a broad triangular shape tapering
shortly to a sharp point. Other mosses have leaves
with a blunt apex and a few species have round leaves.
Another useful character is whether or not the leaves
are all curved in the same direction (falcate) or bent
back from the stem (reflexed or squarrose). Some
leaves also have teeth on the margin, usually visible
only with a hand lens.
NR – nationally rare; NS – nationally scarce; RDL – Red Data List 2001; S8 – listed on Schedule 8 of
the Wildlife and Countryside Act. Oceanic indicates that this is an oceanic species as defined by Hill
and Preston (1998).
British Mosses and liverworts: a field guide. British Bryological Society (2010).
The first comprehensive colour field guide to bryophytes with good keys and hundreds of photos.
Mosses and Liverworts; Gordon Rothero (2005). A brief, general introduction to Scottish bryophytes,
part of the ‘Naturally Scottish’ series published by Scottish Natural Heritage, Battleby.
Bryophytes of native woods – a field guide to common mosses and liverworts of Scotland’s native woods.
Carol L Crawford (2002), Native Woodlands Discussion Group. A small booklet with good colour photos.
Mosses and Liverworts. New Naturalist 97, Porley RD & Hodgetts NG, (2005). Collins.
An accessible account of our bryophyte heritage with a good section on woodlands.
The geographical relationships of British and Irish bryophytes; Hill MO & Preston CD (1998). Journal of Bryology, 20: 127-226.
Colour. Colour and texture are all-important field
characters. Many species have a particular shade,
admittedly usually of green, which coupled with
the structure of stem and leaf, gives a texture which
is what the eye picks up from a distance. Another
important colour is that of the main stem; when
the leaves are dry they become opaque and it may
be necessary to scrape away some leaves with your
fingernail to see the stem colour.
Curve-leaved Bow-moss (Dicranodontium uncinatum)
Photoset above - A variety of moss-leaf shapes, clockwise
from top left: Dotted Thyme-moss (Rhizomnium
punctatum), Catherine’s Moss (Atrichum undulatum),
Little Shaggy-moss (Rhytidiadelphus loreus), Yellow
Fringe-moss (Racomitrium aciculare), Common Striated
Feather-moss (Eurhynchium striatum), Cypress-leaved
Plait-moss (Hypnum cupressiforme).
Nerve (or costa). A very useful character is whether
the moss leaf has a nerve or not. The nerve (or costa)
is a thickened rib of tissue running up the centre of
the leaf which looks like a dark line if the leaf is held
against the light and viewed with the hand-lens. It
usually extends beyond halfway up the leaf and may
reach the apex.
Moss or liverwort?
Initially this is a tricky question but with a little experience it ceases to be a problem. Thallose liverworts are
easy but leafy liverworts can be passed over as mosses by the uninitiated. In most mosses the leaves grow all
around the stem but in most liverworts the main leaves are in two ranks down each side of the stem, sometimes
with a line of smaller under-leaves below. Most moss leaves are roughly triangular, wide at the base and narrow
to the apex; few liverworts are like that. Moss leaves never have lobes whereas many leafy liverworts do. Most
mosses with round leaves have a nerve; no leafy liverworts have a nerve but a few have lines of cells running up
the centre of the leaf.
Bryophytes of
Scotland’s oceanic heath
British Lichen Society
LIVERWORTS
This Plantlife field guide will help those who want to
go a little further in identifying the carpets of mosses
and liverworts that make our western hills such
special places. This guide deals with species making
up Scotland’s oceanic heath, a globally rare plant
community.
What are mosses and liverworts?
Mosses and liverworts (collectively known as
bryophytes) are two of the oldest groups of land plants
and have had millions of years to evolve a variety of
species that have colonised almost all habitats apart
from the sea. Most have a simple structure with a
main stem and more or less frequent branches covered
in leaves. They do not have roots but absorb water
and minerals directly into the (usually) single layer of
cells in the leaves. Most bryophytes are some shade
of green but the liverworts in Scotland’s oceanic heath
are usually strongly coloured, ranging from yellow and
orange, through to reds and purples, to almost black.
What is Scotland’s oceanic heath?
Oceanic heath is a neglected habitat of global
importance. Heather and blaeberry are major
components but what makes oceanic heath special
is its ground layer of mosses that only thrive in the
oceanic climate of the hills in the west of Scotland.
This ground layer is also home to a diverse flora of
large leafy liverworts that have a highly restricted
global distribution. These rare liverwort species
normally occur alongside more common species, such
as Woolly Fringe-moss (Racomitrium lanuginosum),
Red Bog-moss (Sphagnum capillifolium) and
more widespread liverworts like Taylor’s Flapwort
(Mylia taylori) and Orkney Notchwort (Anastrepta
orcadensis).
This habitat is also known as ‘Scottish liverwort heath’,
the ‘Northern hepatic mat’ or the ‘oceanic-montane
heath’.
Why is Scotland’s oceanic heath important?
Oceanic heath is globally rare. In Europe, it is only
well-developed in Western Scotland, western Ireland
and, to a much more limited extent, in SW Norway.
Globally, some of the same species occur in a similar
community above the tree line in the Sino-Himalaya
and North-west America.
Most of the constituent liverwort species have a
remarkably disjunct global distribution. For example
Cloud Earwort (Scapania nimbosa), also occurs in W
Ireland (rare), SW Norway (one site) Nepal, Sikkim and
Yunnan. The community is also so limited in its UK
distribution that most species are nationally scarce
and some are nationally rare. Northern Prongwort
(Herbertus borealis) is limited to just one site in
Europe on Beinn Eighe and Lindenberg’s Featherwort
(Adelanthus lindenbergianus) has one site on Islay
(elsewhere in Europe only in W Ireland). We are still
finding out more about this remarkable community,
with molecular work revealing two new species in the
past few years.
This habitat has a patchy distribution from Islay in
the south, up the west coast to Ben Hope, including
hills in the Hebrides with more limited outposts on
Orkney and Shetland. There are also isolated stands
further east on the larger hills extending to the main
Cairngorms. Most sites are on N or NE-facing slopes
from 200m up to 900m where rain falls in excess of
200 days in a year.
The majority of Scotland’s oceanic heath occurs on
moderate to steep slopes with an aspect from NW
through to NE, almost always where there are some
exposed rocks and frequently where the heath has
developed over large block scree. A number of the
lower level sites are quite grassy, with only residual
amounts of heather but such sites probably represent
relicts that were formerly dominated by ericaceous
shrubs and altered by subsequent management.
They usually have frequent Juniper Prongwort
(Herbertus aduncus ssp. hutchinsiae) but only patchy
stands of other species. The higher sites, where
blaeberry is dominant and where Donn’s Notchwort
(Anastrophyllum donnianum) and Alpine Notchwort
(Anastrophyllum alpinum) can occur, are subject
to long periods of snow-lie which may give some
protection from frost.
‘Bryologising’
Although identifying species initially needs a
modicum of determination, it is possible to quite
quickly become familiar with most of the indicator
species for Scotland’s oceanic heath. The lower
stands of this community have the virtue of being
available all the year round and grow in really nice
places. Though some of the species are very distinct,
even from some metres away, the process and the
enjoyment will be enhanced if you get used to using
a hand-lens (at least x10) to reveal the finer features
on which identification sometimes depends. In the
descriptions, where a lens is necessary it is indicated
by (lens). Remember, hand-lens to the eye and move
the plant into focus.
In these guides, English names have been used
alongside the Latin; these are not ‘common names’
in the same sense as those for flowers because they
are all recent inventions and as yet are hardly used
except in publications like this! Latin names should
always be used for recording purposes to avoid any
ambiguity.
Lindenberg’s Featherwort
Orkney Notchwort
(Adelanthus lindenbergianus)
(Anastrepta orcadensis)
Donn’s Notchwort
(Anastrophyllum donnianum)
© Maren Flagmeier
Introduction
Where to look for the oceanic heath
Oceanic, NR, RDL, S8. Leafy liverwort;
size: medium-sized, forming open turfs of
neat, erect stems amongst other bryophytes;
colour: usually dark brown but can be
brownish-green, glossy; leaves: rounded and
the upper margin incurved towards the stem,
all leaves turned down in the same direction;
habitat: on thin peaty soil amongst heather
on NE-facing slopes; note: superficially
similar to Anastrophyllum donnianum and
Anastrepta orcadensis but the incurved
upper leaf margin is unique; currently known
from just one site on Islay.
Wood’s Whipwort
Leafy liverwort; size: medium, usually
growing as an open turf of erect stems
amongst other bryophytes; colour: often a
rather pale green but can be a dull yellow or
brown, frequently has red gemmae at the
stem apex; leaves: rounded but irregular
and usually shallowly lobed at the apex, the
base of the leaf is concave but the upper part
curves away from the stem so that the whole
looks convex; habitat: on thin peaty soil
amongst ericaceous shrubs, in block scree
or at the base of crags on N and NE-facing
slopes, also frequent in heathy woodland and
wooded ravines; note: generally common in
the west and also frequent in this community.
Taylor’s Flapwort (Mylia taylori)
(Mastigophora woodsii)
Oceanic, NS. Leafy liverwort; size: mediumsized but often forming large cushions or
patches; branching: irregular but frequent,
the branches tending to narrow towards the
end colour: usually some shade of yellow
but may be variegated green or brownish;
leaves: two lobes, the upper larger than the
lower but the most noticeable feature is the
margin which has lots of long narrow teeth
(cilia) easily visible with a lens underleaves:
similar in shape to the main leaves but much
smaller; habitat: on thin peaty soil amongst
ericaceous shrubs, in block scree or at the
base of crags on N and NE-facing slopes,
also occasionally in heathy woodland and
wooded ravines; note: confusion only possible
with Ciliated Fringewort (Ptilidium ciliare),
a species of drier heaths which has shorter,
blunt branches.
Oceanic, NS. Leafy liverwort; size:
medium-sized, forming open turfs of erect
stems amongst other bryophytes; colour:
usually dark brown but can be brownish
green, glossy; leaves: rounded-triangular
but concave so that leaves seem narrow, the
apex has a small notch, all leaves turned
down in the same direction; habitat: on
thin peaty soil amongst ericaceous shrubs,
in block scree or at the base of crags on N
and NE-facing slopes; note: the commonest
species of this community at higher
altitudes and locally abundant.
Carrington’s Featherwort
(Plagiochila carringtonii)
Leafy liverwort; size: medium to large,
usually in large swelling cushions; colour:
variable, in unshaded places it often purplishred variegated with yellow and brown, usually
green in shade; leaves: large and round, often
pressed together at the apex and with very
large cells (lens); habitat: on thin peaty soil
amongst ericaceous shrubs, in block scree
or at the base of crags on N and NE-facing
slopes, also frequent in heathy woodland and
wooded ravines; note: a handsome liverwort,
generally common in the west and also
frequent in this community.
Oceanic, NS. Leafy liverwort; size: mediumsized but often forming large cushions or
patches with erect stems; colour: pale or
yellow-green, often whitish when dry; leaves:
round and placed vertically on the stem so
that the upper faces are pressed against
each other so the shoots look flattened, the
upper margin running down the stem where it
joins (decurrent); habitat: on thin peaty soil
amongst ericaceous shrubs, in block scree
or at the base of crags on N and NE-facing
slopes, also occasionally in heathy woodland
and wooded ravines.
Alpine Notchwort
(Anastrophyllum alpinum)
Oceanic, NS. Leafy liverwort; size: mediumsized, forming open turfs of erect stems
amongst other bryophytes; colour: usually
dark brown but can be brownish green, glossy;
leaves: rounded and very concave, forming
a cup-shape, the apex has a small notch, all
leaves turned down in the same direction;
habitat: on thin peaty soil amongst ericaceous
shrubs, in block scree or at the base of crags on
N and NE-facing slopes; note: almost always
with Donn’s Notchwort (Anastrophyllum
donnianum) but much less common, easily
confused with it but the cup-shaped leaves
are distinctive – if you are not sure, then it is
not Anastrophyllum alpinum. Joergensen’s
Notchwort (Anastrophyllum joergensenii) has
only recently been described as distinct from
Anastrophyllum alpinum and is difficult to
separate from it; it is smaller, usually forms
denser turfs and may occur in damper sites.
Prickly Featherwort
(Plagiochila spinulosa)
Oceanic. Leafy liverwort; size: mediumsized but often forming large cushions or
extensive pure patches; colour: yellow- or
mid-green; leaves: rounded but upper
margin rather straight and running down
the stem (decurrent) in a slight curve, apex
and lower margin with spine-like teeth,
aromatic when crushed and inrolled when
dry; habitat: on rocks and trees in shaded
habitats in the west and common in the
oceanic heath community.
Lesser Whipwort
(Bazzania tricrenata)
Leafy liverwort; size: small but may form large
cushions or straggling patches; branching:
frequent thin branches from bottom of stem
(flagellae) pale with tiny leaves colour: usually
mid-green but can be yellowish; leaves:
rounded-triangular and asymmetric with three
small teeth at the narrow apex, often closely
set and overlapping but sometimes widely
spaced; underleaves: rounded and held close
the stem, usually with teeth visible at the apex
(lens); habitat: on thin peaty soil amongst
ericaceous shrubs, in block scree or at the base
of crags on N and NE-facing slopes; note: This
is a widespread species not limited to this
community but frequent in it.
Purple Spoonwort
(Pleurozia purpurea)
Oceanic. Leafy liverwort; size: medium
to large forming loose turfs or straggling
through other bryophytes; colour: usually
a distinctive dark reddish-purple but can be
yellow- or brownish-green in shade; leaves:
complex, bilobed with a smaller, almost
tubular, upper lobe over a large concave
lower lobe; habitat: on thin peaty soil
amongst ericaceous shrubs, in block scree
or at the base of crags on N and NE-facing
slopes, in wet heath, on blanket bog, also in
heathy woodland and wooded ravines; Note:
Unmistakeable, frequent in this community
but also abundant in wet heath and mires.
Arch-leaved Whipwort
(Bazzania pearsonii)
Oceanic, NS. Differs from Bazzania
tricrenata in usually forming denser and
more ‘succulent-looking’ patches, the base
of the leaves widely crossing the stem when
viewed from above; underleaves held away
from the stem and untoothed.
Western Earwort
(Scapania gracilis)
Oceanic. Leafy liverwort; size: medium
sized but often forming large cushions or
extensive pure patches; colour: a rather
dull yellow- or brownish-green; leaves: two
lobed but with the upper lobe bent over the
lower and upper part bent back so it stands
up from the stem, margin usually strongly
toothed (lens); habitat: on thin peaty soil
amongst ericaceous shrubs, in block scree,
on acidic rocks and trees; note: a common
western species often present and locally
abundant in stands of Scotland’s oceanic
heath at lower levels.
Juniper Prongwort
(Herbertus aduncus ssp. hutchinsiae)
Oceanic. Leafy liverwort; size: medium-sized
with slender stems but often forming deep,
dense cushions or large straggling patches;
branching: frequent thin branches from
bottom of stem (flagellae) with tiny leaves
colour: usually a distinctive reddish- orange
colour but can be green or yellow green tinged
with red; leaves: triangular but deeply divided
into two long, pointed lobes, usually all turned
in the same direction underleaves: similar in
shape and size to the main leaves; habitat:
on thin peaty soil amongst ericaceous shrubs,
in block scree or at the base of crags on N and
NE-facing slopes, also in heathy woodland
and wooded ravines; note: confusion is only
possible with the next species or with Straw
Prongwort (Herbertus stramineus), another
oceanic species but one which favours more
base-rich sites.
Cloud Earwort
(Scapania nimbosa)
Oceanic, NS. Leafy liverwort; size: medium
sized, usually in small patches mixed with
other bryophytes and only rarely forming
large pure patches; colour: usually a purplishred, rarely reddish-green or orange; leaves:
two lobed and the lobes divided almost to
the base, the smaller upper lobe bent flat
over the lower and both lobes tapering to a
rounded apex, margin with long curved teeth
(lens); habitat: on thin peaty soil amongst
ericaceous shrubs, in block scree or at the
base of crags on N and NE-facing slopes; note:
easily distinguished from Bird’s-foot Earwort
(Scapania ornithopodioides), with which it
usually grows, by the colour and long, curved
teeth on the leaves.
Northern Prongwort
(Herbertus borealis)
Oceanic, NR, RDL. Distinguished from
Herbertus aduncus ssp. hutchinsiae
by its usually bright orange colour, the
more regularly curved and asymmetric
leaves, smaller underleaves and by the
numerous flagelliferous branches; note:
currently known only from Beinn Eighe,
its only European site.
Bird’s-foot Earwort
(Scapania ornithopodioides)
Oceanic, NS. Leafy liverwort; size:
medium to large, usually in small patches
mixed with other bryophytes and only
rarely forming large pure patches; colour:
usually a characteristic ‘liver’ red colour;
leaves: two lobed and the lobes divided to
the base, the smaller upper lobe bent flat
over the lower and both lobes tapering to a
rounded apex, margin with straight teeth
(lens); habitat: on thin peaty soil amongst
ericaceous shrubs, in block scree or at the
base of crags on N and NE-facing slopes,
also occasionally in heathy woodland and
wooded ravines.