Orchid Habitats: Chalk lands…
This story relates to different Orchid species and very different
habitats encountered on days off mainly north and south of London.
It’s like a busman’s holiday and it has been a pleasure to meet new
species and the devoted people who care for them. Long may
Botanical tourism thrive between Ireland, Britain and Europe.
Shakespeare Cliff, Kent
This is a impressive area of the Chalk cliffs near Dover where an edible plant, Rock Samphire, was gathered in the
past by people hanging from ropes over the cliff's edge. Shakespeare made a reference to this ‘dreadful trade’ in
his play, King Lear, and the cliff itself is now known as ‘Shakespeare Cliff’. There is a small railway line, in
operation since 1844 running at the base of the cliff, just visible as the double tunnel in the background of the
image above.
Samphire Hoe is new land on the seaward side of the railway line which was created by dumping of chalk
material from the Channel Tunnel excavations. The land thus created was later opened to the public as a Country
Park and appropriately named Samphire Hoe (after the plant). It is accessed by road via a steep tunnel from the
top of the cliffs which exits onto the Hoe next to the railway tunnels.
This is an exciting and unusual area of about 30 hectares looking out over the Channel towards France and has
many interesting plant species including the Early Spider Orchid, Sea Lavender and Samphire. It is a haven of
peace and quiet enabling a new ‘orchid habitat‘ and tourist destination and was a great way to usefully treat the
spoil from the Channel Tunnel. The Chalk cliffs along the south coast are very susceptible to erosion by the sea
but this stretch is well protected by this new land of Samphire Hoe!
Selborne, Hampshire
Selborne is on the north edge of the South Downs National Park, and the area (especially on a sunny summer’s day) is charming. Though the
name Selborne is mostly associated with Gilbert White and his research on birds and other animals in the 18th century, this location has a
number of important sites for orchids. Noar Hill, not far from the village of Selborne, is a small, but fascinating area of chalk grassland. At
first, the site looks rather unkempt, with scattered hillocks with scrub and small trees and chalky slopes. The site of medieval chalk workings
which were used as fertiliser, there are now numerous little hills, dells and shallow valleys where the chalk was quarried. The site has small
trees of beech and hazel, and much scrub. On the very hot July day when this site was visited, the grass was parched except under the trees.
But there was a profusion of flowers, including the rare Musk orchid, Chalk Fragrant orchid, Twayblade, Knapweed Broomrape and
Clustered Bellflower. It was the Musk orchid which was the main attraction though…
Knocking Hoe, Bedfordshire
This is a stunning Nature reserve at the north end of The Chiltern Hills on chalk grassland. There is a wonderful collection of rare and interesting plants including the Pasque flower, Spotted Catsear and Clustered
Bellflower. But the one that draws so many botanists to here is the rare Burnt Tip orchid, which is found in only a few sites in Southern England. In the image BELOW, left, there is a fenced-off area at the far end of the
grassy ridge where the majority of the Burnt Tips are protected from disturbance.
Some English orchids…
On trips to England (specifically), searching for orchids and other interesting plant life has been an enjoyable pastime for us. Depending on the location, there are nearly always good references to be be
found online or in books which can be researched beforehand, which lead us to a local rarity or an particularly interesting species. It is exciting to search for an orchid which does not occur in Ireland, and
take the photographs, and details of the day, away with us as happy memories of a particular trip. This report just describes a few of our jaunts in recent years. Sometimes, it was the particular orchid
species we were seeking, other times it was the attraction of a well-documented and well-recommended Nature reserve or local area where many orchids species and other plants were common. The
chalky geology of southern England is a wonderful environment for orchids and one which does not occur in Ireland. But, Ireland does have its own rare species and it is lovely to meet botanists from other
countries who visit sites in Ireland for this purpose. We always like to hear from you, just as we enjoy meeting botanists on our trips to English sites!
The Early Spider Orchid was found in small numbers on the
steep cliffs seen on the image above. It’s a rare species,
found in only a few areas in Kent and other southern
counties (Sussex, Hampshire and Dorset). However, since
the creation of Samphire Hoe, this orchid can be found in
large numbers on the grassland in front of the cliffs. Some
hundreds were starting to flower when these images were
taken (April 21st) but we are told they occur in thousands…
Musk Orchid
Herminium monorchis
A rare very delicate yellow orchid of old
quarries in the south of England…
Chalk Fragrant Orchid
Gymnadenia conopsea
A delicate Fragrant Orchid of chalk
landscapes, quarries or downs.
Fulbourn Fen Cambridgeshire….
This was a lovely peaceful little Nature reserve, encompassing some old meadows and chalky fenland area. Visited in May, the
fen was only slightly damp, as the weather had been very warm. Along with a few interesting Adders Tongue Ferns, were
scattered a few of the orchids pictured here. Now, these orchids gave us a bit of a problem. They were very sturdy plants, like
the Early Marsh D. coccinea, but not quite the same? We figured that they were Dactylorhiza praeternissa, the Southern Marsh
orchid which is a species that doesn’t occur in Ireland.
The flower heads were still just buds, so it wasn’t possible to view the flower structure On most of the specimens the leaves were
unmarked, but one (RIGHT) had markings which were not spots, but purplish oval shaped patterns on the upper side of the
leaves only. (We’ve seen similar sort of markings in the leaves of Dactylorhiza cruenta, which is a much more slender orchid, and
which we get in Ireland). If you are familiar with Southern Marsh orchids, please do let us know if this identification is correct?
Southern Marsh Orchid
Dactylorhiza praeternissa
A common Marsh Orchid, found in Northern
and Central Europe, absent in Ireland
A rare plant in England, this
tiny, fragile orchid is
common in mainland Europe
but not found in Ireland.
It is greenish-yellow, and has
no spur. The flower points
downward, and and petals
and sepals are rather thin.
and unlobed. Hundreds were
seen growing on this Noar
Hill site in early July. Image
on RIGHT shows one clump
of about ten Musk orchids in
a small patch of grass.
This delicately coloured
Chalk Fragrant orchid, on
RIGHT, is relatively common
in chalk grasslands and
Downs in England. It has the
longest spur of the Fragrant
orchid species and, like the
others, has a clove-like
scent. The flowers are often
widely separated which
shows off the long, very
curved spur. This was an
exceptionally beautiful
specimen!,
White Helleborine
Cephalanthera damasonium
A common orchid in most of Europe…
Burnt Tip Orchid
Neotinea ustulata
This rare orchid is found in chalk
grasslands and has a distinctive maroon
coloured tip to the budding flowerhead.
This is quite a small orchid ; these
specimens weren’t more than 10cm
high. However, these photographs were
taken in May when the orchids were not
fully developed as can be seen by the
strongly dark wine-coloured buds on
the tip of the plant. This is what gives
the orchid its name as the tip looks
‘burnt’. It actually looks much more
attractive at this stage than when the
flowers are all open, as the flowers look
much paler then…
The lip, or lower petal is 3 lobed, with
the middle lobe split, and is white with
wine spots. It looks like a cartoon man
shape with the upper petals and sepals
forming a hood above, the ‘body’ being
the divided lip below.
Homefield Wood is a pleasant area of woodland in Buckinghamshire at the south east edge of the Chiltern Hills. Near the access road, there is an area of coniferous
trees, not yet fully mature and with good areas of sun and shade beneath. This was welcome in a sweltering hot early summers day! Many broad and little paths
spread throughout this wood, and it appears to be a popular place for walkers. Beyond the wood, and through an open stretch of cut-over forest, lay the protected
sanctuary for these rare orchids. This is one of only a couple of sites for the Military orchid. A very charming and informative book describes the site. The Orchid
Hunter (RIGHT) written by Leif Bersweden, who we met in Ireland, is both a delightful story full of years of Natural History wisdom and interesting personal memoirs!
Having already explored other sites for orchids around the Chilterns, this hot day seemed like an ideal opportunity to see if we could find this orchid, though we knew
it was very early in the season…
There were some scattered Burnt
Tip orchids growing along the top
of the far ridge (see image
ABOVE) but the majority were in
an enclosure marked with little
red flags. This site is well
protected by local botanists and
these measures will help to
protect them from grazing
animals as well as disturbance
from visiting botanists and
photographers!
The Reserve is really worth a visit
to see this lovely rare orchid, as
well as many other interesting
plants that are found here.
But, before we left the area, we
just had to examine the many
impressive White Helleborines,
which were flourishing in the
Beech woods which stretch
between the site and the main
access road. Pictured RIGHT,
these White Helleborines are
common around Europe, though
unfortunately not in Ireland!
Early Spider Orchid
Ophrys sphegodes
A rare and sturdy little orchid of chalky
sites in southern England
Beyond the wood and cut-over forest
the ground opened out into an area
of grassland, with scattered copses
of trees. Next to one of these copses
was a deep dell, which was securely
fenced off. (BELOW LEFT). This was
the protected site for this rare
orchid. There were little walkways
beyond the entry gate and a viewing
platform, presumably for visiting
botanist groups and researchers.
Even looking with binoculars into
this enclosure, we were disappointed
not to see any evidence of these
orchids.
However, as we circled around the
enclosure, we noticed a lightly
fenced area with an open gate to a
smaller patch. Carefully tip-toeing in,
we spied some unusual greyish
purple buds showing in the short
grass. We’d found it! The plants were
really at an early stage, with one or
two flowers appearing on a few of
the plants.
It’s another ‘man-like’ orchid, the
hood at this stage looking like soft
greyish velvet, the labellum or lip
edged in purple, with reddish-purple
‘tufts’ along the centre. There
appeared to be quite a number of
the orchids in this small patch, but
only three had a few flowers open.
More information on the species
from the BSBI at… Orchis_militaris
Biology and Distribution
World Distribution
Britain (barely), Central Europe and
Asia as far east as the Caucasus and
Siberia. Some superb photographs
from the Czech Republic can be
seen on Botany.cz
LEFT
Homefield Wood
Home to one of Britain’s rarest orchids.
RIGHT
A freshly emerged specimen in early May beside
the main habitat for the species in an old quarry.
Homefield Wood
Military Orchid
Orchis militaris
A very rare orchid of stunning appearance
and colouration!
Do enlarge this image as it contains an impressive number of very small plants
The orchids in this site were not yet flowering but in another smaller patch nearby many striking plants were newly emerging and we had easy access to the specimens.
This is a good example of helpful voluntary conservation work, protecting the orchid as well as letting observers approach the area without doing any harm. Many thanks!
Evolution and Phylogenetics of Orchids: With Orchis mascula and Orchis militaris as examples
In recent investigations and online research we have become, again, interested in learning more about the
evolution of species and the change of structures that seem to contribute to this family being so successful.
(Development of pollinia, epiphytic adaption, root development and expanded distribution in both tropical and
mountainous regions. etc.) Much research on the group seems focused on analysis of the genome as a definitive
means of allocating apparently similar plants to different species and very varied specimens (particularly in
regard to colour) to the same species. We feel there is still room for traditional field identification of species and
that the morphology of a plant is important, as is its genotype.
This view has been brought to the fore in recent work on the Flecked Marsh Orchid which is alternatively known
as Dactylorhiza incarnata ssp cruenta or more simply Dactylorhiza cruenta, its former name and one which is well
warranted based on phenotype and distribution. The evolution and migration of the Dactylorhizids in general is
discussed in our study of Cruenta, particularly the way they adapted to climate change (the Alpine orogeny) and
developed adaptations to a colder climate that held them in good stead in their rapid subsequent migration
across Eurasia. The Military Orchid (Orchis militaris) is not of the same genus but its distribution and occurrence
seems somewhat similar to D. cruenta.
Literature A:
Phylogeny of orchid groups investigates the adaptations they have made that make the various species so
successful in the world… BELOW we quote an article recently published online by The Royal Society.
Orchid phylogenomics and multiple drivers of their extraordinary diversification
In an extract from their Introduction they say…
“Orchids form the largest family of flowering plants, with over 880 genera and 25,000 species; they comprise roughly 8%
of all vascular plant species and grow in a wide range of habitats worldwide [1,2]. Essentially all temperate orchids are
terrestrial, but most orchids inhabit tropical forests and over 80% of those are epiphytes. All orchids rely on fungi for
germination and carbon capture in the protocorm stage, and in many taxa this mycorrhizal association remains
obligate for life [3].”
Givnish TJ et al. 2015 Orchid phylogenomics and multiple drivers of their extraordinary diversification.
Proc. R. Soc. B 282: 20151553.
Literature B: A further detailed and helpful source is available from The Journal of Botany at Oxford.
Phylogenetics of tribe Orchideae (Orchidaceae: Orchidoideae) based on
combined DNA matrices: inferences regarding timing of diversification and
evolution of pollination syndromes
Luis A. Inda1,*, Manuel Pimentel2 and Mark W. Chase3
This provides detailed records of the evolution path and the current phylogeny of many of the European
Orchidaceae A lot of the DNA analysis is very technical but charts included show the close relationship of 2 Orchis
species, namely O. mascula (Early Purple) and the Military Orchid (Orchis militaris) We show that relationship in
images of young plants shown RIGHT. Download above Study… it’s amazing!
Military Orchid, O. militaris Cambs., UK.
15th May 2019
Early Purple Orchid, O. mascula Roscommon, Irl.
20th April 2020
These two orchids are similar. They are sturdy, quick growing, flower early and have radially scattered flowers.
The leaves and stalk initially are both straight and sturdy with broad pointed leaves clasped tightly to the stem.
But, there are differences too. In particular the spurs are different with the Early Purple being unusual in pointing
upwards and being long and thin whereas its cousin’s is stubby and pointing downwards. Also, whereas the
colouration is similar to some degree, the labellum is much more ornate in the Military Orchid having the
appearance of a human figure which is why it is one of the four anthropomorphic orchids found in Britain.
Their occurrence is also markedly different. The Early Purple is abundant and widespread in both countries
whereas the Military Orchid is unknown in Ireland (so far… specimens in Finland were misdiagnosed as Early
Purple for many years) and very rare in England. Why? Some of the answers may lie in the Phylogeny Table
contained in Literature B and a small extract of which is reproduced BELOW…
Relationships:
So how are these two species related and why do they have such different distributions. Firstly, it is clear that all
members of a genus, like Dactylorhiza, are not identical and have a great number of species occurring around
the world. Taxonomical classification of plants regularly changes based on observation and genetics.
Fortunately the Orchis genus is a small one and the pathways are simpler. If we consider O. anthropophora (Man
Orchid) at the bottom of the list to be the 2nd cousin of O. militaris then O. mascula can be called a more distant
relation but all are within the Orchis clan and the Orchidaceae family. Does that make any sense?
What features define the genus Orchis?
Several broad leaves on lower stem with some smaller ones above, sometimes spotted. The petals and sepals
often form a helmet like structure, 5 in the case of militaris and 3 in the case of mascula. Labellum with two
lateral lobes and a larger terminal lobe and usually 2-3 lobed at its tip. Spur may be short or long (as above) or
absent.
There is clearly a similarity between these two orchids especially when the plants are seen with young buds. It is
strange that one is so common and the other is so rare. One of the flukes or anomalies of incident and evolution?
This is just a small section of the
DNA based relationship map for
the tribe Orchidaceae showing
the relative position of mascula
and militaris species within the
Orchis genus. The full chart is
available in the PDF provided by
the Authors. (LEFT)
Phylogeny… the relationships among different organisms or groups and their evolutionary development.
A free tool for Field Naturalists.
The above Report also has a very interesting 2nd feature. All
groups of orchids reproduce in many different ways — self-
fertilisation, cross fertilisation, various fertilising agents,
autogamous, and some other more exotic processes. These
affect the distribution and the survival of a species. e.g. Bee
Orchid v. Fly Orchid!
We cannot reproduce that table here but Link to the Study
and at the middle of the report you will find a Table named…
Phylogeny and Evolution of the European orchids.
TABLE 1. Pollination-related characters analysed:
This describes pollination methods for all Orchids studied.
Species.. Nectaries.. Syndrome.. Pollinators… Labellum area
Samples:
O. mascula no food deception female Bees 78sq.mm.
O. militaris no food deception Bees 62.5sq.mm.
SPECIES: The name of the Orchid. Most species are listed.
NECTARIES: Neither species studied provide nectar.
POLLINATION SYNDROME:
The main way an orchid effects pollination, Food
Deception/Food Reward/Sexual Deception/Sleeping
Site/Autogamous. Each species is identified by syndrome.
POLLINATORS:
Bees/Male Bees/Female Bees/Wasps/other Hymenoptera/
Coleoptera/Diptera/Lepidoptera
LABELLUM AREA: (Length x Width)/2 in sq. millimetres.
A large labellum is an aid to easy fertilisation!
LEFT: The
protected site for
Military Orchids.
A F T E R W O R D S
Comparison of two related Orchis spp.
The specimen pictured ABOVE was sturdy,about 10cm high.
Many of the other specimens were barely pushing above
the soil.
Why Chalkland?
WildWest.ie is based in Ireland. There is very little Chalk in Ireland for
simple geological reasons. There are vast areas of Limestone and
other alkaline strata… but no chalk! So why fewer lime loving orchids?
This may be the reason why none of the plants listed here are found
in Ireland and why we love our chances to botanise in southern
England (where chalk is everywhere) and meet and talk to people
about their orchids and our (Irish) orchids. It is a common bond….
A young Orchis mascula in bud
KNOCKING HOE KNOLL...
Melbourn Rock Member.
Chalk. Cretaceous bedrock (90 to
101 mya.) Hard to very hard off-
white, blocky fractured chalk with
numerous nodular chalk beds and
thin spreading marls.