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THE
PLANTS OF THE WET PASTURES
Everyone
who has climbed on the higher Scottish mountains must have been struck by
the beautiful, green, mossy springs which occur, like oases, among the
dry, somber rocks and boulders. The sides of streams and rivulets, so
often obscured by rank vegetation in the lowlands, are here delicate green
carpets of moss and golden saxifrage, through which the water gurgles or
under which it disappears. These areas are delightful spots to explore,
for it is here that we shall find many characteristic plants of the
mountain pastures, plants which cannot tolerate dryness, but revel in
plenty of water at their roots. They include the Starry Saxifrage, the
Alpine Willow-herbs, the Alpine Stitchwort and several others.
Large
areas of boggy and marshy land occur in the mountains. The bogs with
their peaty soil, will be dealt with in a separate chapter, as they are
characteristic of many of the lower areas. The damp pastures, where
bog-mosses are not abundant, support a varied population of grasses,
rushes and sedges, as well as other plants such as the Alpine Saussurea
and the Alpine Willows. The peaty soil of the bogs and moorlands is not
so evident in these areas, where owing to the slope and hence the better
drainage, the water tends to be running rather than stagnant and the soil
less waterlogged than the typical bog lands.
THE
SAXIFRAGES
 Yellow Mountain Saxifrage (Saxifraga aizoides)
I first
made the acquaintance of this beautiful saxifrage at the head of Glen
Nevis, where I have found many interesting mountain plants. A small
waterfall came tumbling down the steep mountain side, dashing itself
against rocks and boulders in clouds of spray as it rushed down from the
springs near the summit of Ben Nevis. I climbed up beside this glistening
cascade, where my eye was caught by several bright golden patches at the
water’s edge. Scrambling down I found that the patches were several large
tufts of the Yellow Mountain Saxifrage, their leaves bedewed with spray.
They grew out of the damp rocks and hung down their face, forming a
perfect, natural, rock garden.
It has a
short stock, covered in the old leaves of past years. From this stock
arise, or rather descend, several flowering stems which may attain six
inches, or even more, in luxuriant specimens. They are clothed in rather
thick, deep green, ovate leaves which are very seldom toothed or lobed.
They are surmounted by a panicle of five to perhaps a dozen or more
beautiful, golden yellow flowers.
If we
study the flowers, we shall find that they appear to have ten petals.
This is because the sepals are about the dame length as the petals and are
of the same golden colour. This is another device to make the plant more
conspicuous. AT the base of each petal is a deep yellow spot and it is
here that the nectaries are situated. The anthers are bright red.
The
flowers are pollinated by bees, flies and butterflies as described under
S. oppositifolia (see page 15
It is
quite a common plant in the Highlands, and one can be almost sure of
finding it among damp rocks and beside streams and springs. It does not
attain such high altitudes as most of the alpine saxifrages.
 Starry Saxifrage (Saxifraga stellaris)
This
plant is a typical, rosette saxifrage (see p. 18) and is quite unlike
S. aizoides and S. hypnoides in habit. The short main stock is
crowned by a rosette of egg-shaped leaves, which are of rather a thin
texture and are usually toothed near the apex. They are not pressed close
to the ground as in many rosette plants, but are semi-erect. As this
plant lives in bogs and springs, this upward tendency probably keeps the
under surface, with its vital breathing pores, from becoming waterlogged.
Each
rosette sends up a fine, flowering shoot which is bare of leaves. It is
surmounted by a panicle of small, white flowers; each one is exactly like
a bright star and is very conspicuous. Two yellow spots are found near
the base of each petal and act as honey guides.
This
little plant loves the bogs, springs and damp places of the mountain sides
and attains considerable elevations. It is common on our Scottish
mountains above 2,000 feet.
Mossy Saxifrage (Saxifraga hypnoides)
This
plant forms dense tufts of green leaves from which spring the flower
stalks. The stock is covered by the brown, dead leaves of past seasons,
and sends out many creeping branches which are fairly long when terminated
by the flower stem; or short, when barren. The branches are covered with
many small leaves which are usually three-lobed. The barren shoots form
dense tufts of leaves, but bear no flowers. The flower stems are tall and
devoid of leaves and are surmounted by several large, white flowers.
This
plant varies greatly and at high altitudes becomes very tufted, the
flowers becoming smaller and the whole plant much more like S.
caespitosa (see p 17), which some authorities think is a high alpine
variety of S. hypnoides.
THE
ALPINE WILLOW-HERBS
The
willow-herbs are very common plant throughout the whole of Britain, and in
the Highlands such species as the Rose-bay and the Hairy Willow-herb are
to be found in the glens and lower regions. Two species, however, are
confined to the high mountain pastures of the Highlands; they are the
Chickweed-leaved Willow-herb (Epilobium alsinefolium) and the
Alpine Willow-herb (Epilobium alpinum).
They are
usually found along the edges of brooks and streams and in wet places at
altitudes of from 2,000 to 3,000 feet. They are both very common in the
Highlands, although often overlooked, as they are by no mean conspicuous.
The
Alpine Willow-herb is a small, little branched plant with a creeping
rootstock which sends up short leafy stems in the autumn; these are called
scions or offsets. These scions survive the winter and form the new
flowering plant of the following year; they are rather long and slender
and are covered with small leaves.
The
flowering plant is often branched at the base, but each stem is unbranched
and attains four to five inches in length, running close to the ground and
only becoming erect towards the extremity, where it produces a raceme of
flowers which is often reduced to one or two solitary blooms. The stems
are covered with small, glabrous leaves.
The
flowers are large in comparison to the size of the plat and terminate the
long cylindrical ovary, which is about one inch in length. They consist
of four pinkish petals which are inserted on the calyx tube and in which
are included the stamens and stigmas. Nectar is secreted on the summit of
the ovary and as the anthers mature before the club-shaped stigmas,
self-fertilization is impossible. Small bees are the chief visitors.
In the
autumn when the flowers have faded, the long ovary splits and liberates
the seeds which are terminated by a tuft of long, silky hairs. These
hairs support the seed and it sails along in the wind for long distances.
For this reason the Alpine Willow-herb is a widely distributed and common
plant.
The
Chickweed-leaved Willow-herb is a more luxuriant plant than the preceding,
being much more branched and covered in larger, ovate, toothed leaves.
The flowers are also larger and arranged in leafy racemes. The offsets
are often underground, consisting of bud-like swellings. The seeds are
distributed as in the preceding.
THE
ALPINE CERASTS
Around
the green, mossy springs of the high mountain sides, one may often come
across the delicate, bright green, cushion-like tufts of the Alpine
Stitchwort (Cerastium cerastoides), starred with pure white
flowers, especially if one is climbing among the higher mountains of
Breadalban, Lochaber, or the far north. It is a beautiful little plant
with its intricately entwined, short, perennial stems covered with tiny,
opposite leaves of a bright, shiny green, washed continually by the spray
of the tumbling torrents by which it loves to dwell. The cushion-like
tuft survives the long, hard winter beneath the snow. IN the spring the
cushion send sup many weak flowering ste,s which produce tow or three
pairs of small, opposite leaves and are terminated by one or two large,
white flowers. As in the case of the Moss Campion, this cushion
arrangement with its many flowering stems makes the flowers much more
conspicuous than they would otherwise be.
The
flower consists of five cleft petals surrounded by an equal number of
sepals, which are only half as long. It secretes much nectar and the
glistening drops are plainly visible. The ten stamens shed their pollen
one by one before the three styles have matured. The chief visitors are
flies, small bees and thrips. The seeds, being very small and light, are
blown to a considerable distance by the winter gales.
 Alpine Cerastium (Cerastium
alpinum)
This is
another very common plant of the damp mountain pastures. It is usually
found in less moist situation than the Alpine Stitchwort, such as grassy
pastures, damp screes and clefts in damp rocks. Like the preceding it has
a loose, cushion-like tuft of perennial stems covered with small leaves,
which in some varieties are almost glabrous, and in other are covered with
a thick woolly coat of hairs which protect the plant against cold and
drought. The tuft sends up many short, flowering stems, which are clothed
by three or four pairs of oval opposite leaves. Each stalk is terminated
by a single large, conspicuously white flower, much like that of the
Alpine Stitchwort, but larger. The flower is similarly pollinated.
THE
MOUNTAIN WILLOWS
The
mountain pastures are the home of many species of willows which are more
or less adapted to high, exposed situations and damp or west conditions.
They have not become so typically alpine in their habit as the high alpine
willows (Salix herbacea) and (Salix retuculata) (see p.
22).
I do not
intend to describe the many varieties and hybrids to be found on the
Scottish mountains, but simply the main forms from which most of them are
derived. Anyone wanting more detailed descriptions of this numerous and
difficult genus must refer to one of the many monographs which have been
written.
The main
species to be found in the Scottish mountain pastures are the Tea-leaved
Willow (S. phylicifolia), which is fairly widely distributed in the
Highlands, the Downy Willow (S. Lapponum), a much rarer plant
confined to higher altitudes than the preceding, the Woolly Willow (S.
lanata), confined to a few high, rocky glens, and the Whortle Willow (S.
Myrsinites), confined to higher mountain pastures.
Unlike
the tall, often tree-like willows of the lowlands, the mountain willows
are rarely more than shrubs, and in exposed situations are often closely
procumbent to the soil, especially the Whortle Willow, but attaining two
or three feet when grown in sheltered spots.
A close
examination of various types of S. phylicifolia and S.
Myrsinites show that they merge almost imperceptibly into one another,
so that the latter may indeed be only a high mountain variety of the
former.
They
agree in having ovate leaves (although the commoner forms of S.
Myrsinites have orbicular leaves) which, while they are silkily hairy
when young, become devoid of hairs on the young leaves probably protect
their tender tissues from frost and damp.
The
catkins of S. phylicifolia are slender, rarely an inch in length.
The males are without stalks, but the females are on short, almost leafy
stalks. They are rather silky. IN the case of S. Myrsinites the
catkins, both male and female, are produced on short, leafy stalks and are
also silky.
We can
find S. phylicifolia along the edges of streams and in damp
hollows, which give some shelter from the wind, at considerable
altitudes. As we ascend it is gradually replaced by S. Myrsinites
which is confined to the higher pastures.
The other
two species, S. lanata and S. Lapponum, differ from the
preceding by being thickly covered with hairs at maturity. They are
stout, bushy, shrubs to be found in rocky places at high elevations and
are definitely Arctic types. The former has leaves which are thickly
covered on both sides with dense, silky hairs which are very beautiful,
and make a complete protection against the drought, damp and cold. In the
latter the coat is much thinner and is composed of a cottony down. Its
catkins are covered with long, silky hairs and are an inch in length,
becoming nearly two inches in length after flowering. Thos of S.
lanata are very beautiful objects, being covered with long, silky,
golden hairs and being nearly one and a half inches in length. After
flowering the females attain a length of three inches.
As we
have already remarked these descriptions apply in a general fashion only,
each species giving rise to so many varieties and hybridizing so freely
with each other that definite identification is almost impossible. They
are interesting in composing a part of the special mountain flora of the
Scottish Highlands and an interesting collection may be made showing the
gradation of varieties from one particular species to another.
OTHER
PLANTS OF THE WET PASTURES
Mountain Sorrel (Oxyria digyna)
This
plant belongs to the same family as the lowland Docks and Sorrels and is
quite a common plant in the damper portions of our higher mountain
pastures.
It is
noticeable because of its rosette of smooth, dark green, kidney-shaped,
radical leaves which terminate a long leaf stalk. The rosette sends up a
slender, leafless, flowering stem which is terminated by a branched raceme
of many, small, greenish flowers.
The
flowers possess no conspicuous petals or sepals as do most alpine
flowers. They are visited by flies for the sake of their pollen (as they
secrete no nectar) and so cross-pollination may be effected by them. Wind
pollination is probably the plant’s surest means of cross-fertilization.
Alpine Meadow-rue (Thalictrum alpinum)
This a
quite a common plant in damp pastured at fairly high altitudes throughout
the Highlands. It belong to the Ranunculus Family, of which several
plants such as the Marsh Marigold, Wood Anemone and Glove Flower are found
in various situations, but the Alpine Meadow-rue is the only species in
the British flora found at high altitudes.
It is a
dainty plant with its beautifully-cut leaves and delicate flowering
system. The leaves are mostly radical, each stalk being divided into
three or five branches which are clothed with small, roundish, glabrous
leaflets. From the midst of the leaf stalks arises the simple, leafless
flower stalk, which is usually four to six inches high and terminated by a
few drooping flowers.
The
flowers possess a small, yellowish calyx, but have no petals, the numerous
long, golden stamens being the flower’s chief advertisement. Flies and
pollen-seeking bees visit the flowers for the pollen so liberally provided
(no nectar is secreted), but it is probable that the plant is more
dependent on wind pollination. The long stamens, projecting well beyond
the calyx, support this view, as in this position they are exposed to the
wind, which blows the pollen from the anthers to fall upon the receptive
stigmas of nearby plants. When the weather is wet and there is danger of
the pollen in the exposed anthers becoming wet and useless, the anthers
close and so protect the precious dust.
Alpine Saussurea (Sanssurea alpina)
This is
quite a common plant in damp pastures at fairly high altitudes throughout
the Highlands. It belongs to the Ranunculus Family, of which several
plants such as the Marsh Marigold, Wood Anemone and Globe Flower are found
in various situations, but the Alpine Meadow-rue is the only species in
the British flora found at high altitudes.
It is a
dainty plant with its beautifully-cut leaves and delicate flowering
system. The leaves are mostly radical, each stalk being divided into
three or five branches which are clothed with small, roundish, glabrous
leaflets. From the midst of the leaf stalks arises the simple, leafless
flower stalk, which is usually four to six inches high and terminated by a
few drooping flowers.
The
flowers possess a small, yellowish calyx, but have no petals, the numerous
long, golden stamens being the flower’s chief advertisement. Flies and
pollen-seeking bees visit the flowers for the pollen so liberally provided
(no nectar is secreted), but it is probable that the plant is more
dependent on wind pollination. The long stamens, projecting well beyond
the calyx, support this view, as in this position they are exposed to the
wind, which blows the pollen from the anthers to fall upon the receptive
stigmas of nearby plants. When the weather is wet and there is danger of
the pollen in the exposed anthers becoming wet and useless, the anthers
close and so protect the precious dust.
Alpine Saussurea (Saussurea alpina)
This
beautiful plant of the higher, damp mountain pastures is a member of the
great Composite Family, and is closely related to the knapweeds and saw-wort
of our lowland meadows.
Like most
composites it is a perennial with a deep-striking tap-root which gives
rise to a stout stem about one foot high. It produces several large ovate
leaves, which are a shiny green above, but are covered with a thick white,
cottony down beneath, which wears off with age. This down serves the dual
purpose of saving the pores from becoming waterlogged in wet weather and
of protecting the leaves from excess transpiration in times of drought,
which on the high mountain sides can be very severe. The stem and
involucres are also covered in down.
The stem
is terminated by a dense corymbs of small purple heads, which are
protected by an involucre of closely imbricated, pointed bracts, the inner
ones of which are softly hairy. The florets are surrounded by a softer,
feathery pappus which projects beyond the involucre. The flowers are
pollinated as in the case of the Melancholy Thistle (see p. 77)
 Alpine Lettuce (Mulgedium alpinum)
In a few
secluded spots, beside crystal springs and streams high up in the
mountains of Clova and near the summit of Lochnager, we can find one of
our most beautiful and rare mountain plants. It prefers the sheltered
corries to the open hillside, and this is quite natural when one considers
that it may be as much as three feet high and bears large leaves; the wind
of the exposed mountains would soon beat it down and destroy its beauty.
It
possesses a large tap-root which stores up food material during the summer
and allows the plat to pass the winter safely beneath the snow.
>From the
stock arise several large, spreading, smooth, green leaves which are
almost succulent and in which the upper love is very broad and large. The
flowering stems may be over three feet high and are clothed with similar
leaves which, however, diminish in size as the summit of the stem is
approached. The upper part of this stem is covered with glandular hairs
which prevent creeping insect from reaching the flower heads.
The stem
is unbranched and produces a long, narrow panicle (which is almost a
raceme) of several heads of beautiful, deep-blue flowers. The involucre
is narrow and consists of a few small, imbricate bracts. Each head
consists of twelve to twenty deep-blue, strap-shaped florets which are
arranged similarly to those of the Common Sow-thistle, so common as a
garden weed.
The seed
is surmounted by a dirty-white pappus of long, stiff hairs which form an
admirable parachute.
The
flowers are visited by bees who are attracted by the deep-blue florets and
the corolla tubes full of nectar.
Hairy Stonecrop (Sedum villous)
This is a
rather strange little plant, as firstly it is an annual (annuals are very
rare in mountain floras), and secondly it loves the wet, stony sides of
streams and springs, whilst all the other members of this family love dry,
stony places.
It
possesses small erect stems covered with fleshy, cylindrical leaves, which
are usually scattered along the stems.
The stem
is terminated by a few small flowers, which have five dingy-pink or lilac
petals. The flowers are not at all conspicuous and are probably
self-fertilized. Insect do visit them occasionally, however, and nectar
is secreted so that some cross-fertilized seed may be produced. The upper
stem is covered with short, viscid hairs which form a fence against
creeping insect.
This is
not a common plant in the Highlands, being confined to the area south of
the Caledonian Canal.
Melancholy Thistle (Carduus heterophyllus)
This very
handsome species is one of our most beautiful thistles, and it is a unique
experience to climb up into a grassy corrie and find a colony of these
large, dignified plants, their large head of purple flowers contrasting
beautifully with the white, cottony stems and the bright, shiny, upper
surfaces of the leaves.
Its
rootstock is perennial and creeping so that the plants spread, once
established, and soon form colonies. They give rise to tall, stout and
deeply-furrowed stems, which are often four feet tall in sheltered spots,
and are covered with white, cottony wool.
The
leaves are very large and embrace the stem by two small auricles. They
are lanceolate and bordered by very small teeth which, however, are not
spinous as in most other thistles. The upper surface is green and shiny,
but the under surface is thickly covered with white hairs. These prevent
the stomata from being blocked by moisture arising from the wet soil the
plants inhabit.
The stem
is terminated by a large head nearly two inches in width. Its involucre
consists of glabrous lanceolate bracts which are not armed with spines.
The
flowers are pollinated by humble-bees as described under the Spear Thistle
(see Chap. XXI). As in the case of that plant, the seeds possess large
parachutes which carry them long distances over the mountain sides. |
