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The Story of
Orchids
Image.. catasetum pilateum
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catasetums are a genus of orchids which include
around 50 species, and can be found throughout
Central and South America and also the West
Indies.
They have evolved a fascinating way of attaching
pollinia to the visiting pollinator, by
means of a trigger mechanism which can fire the
"super glue" pollinia a surprising distance,
either when it is touched or by a firm vibration
on the flower itself.
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Around 120 million years ago, when the dinosaurs
ruled the land, much of the world was covered by
primordial forest, and plant life was rapidly becoming
diverse, flowering plants were evolving and one of the
first of these was the orchid.
As the world underwent many changes species of both
plant and animal life died out or were replaced, but the
orchid family expanded, populating every corner of the
world except Antarctica, living on trees, rocks, in the
ground or under it, tropical rainforest or lush
grassland, high mountain or bog, they thrived; nothing
seems capable of upsetting their evolutionary process,
indeed it is generally accepted that in the world today,
there are over 35,000 different species of orchid in
existence.
Many myths abound concerning them, the most common of
which is that they are parasitical plants, this is not
so, orchids grow on trees - true, but they do not feed
from them, they use the host merely as somewhere to be.
The above facts must make them one of the most
successful and adaptable family of plants, (which
probably explains their long family history) what they
lack in internal resources, they will try to obtain
elsewhere, some orchids which prefer a more acidic
condition, will encourage ants to live on them, even in
some instances creating suitable chambers for their
guests to live in, and in addition to warding off their
enemies, the ants increase the acidity on the plant
through their own use of formic acid as a defence
system.
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Orchids have known all about the birds and
bees far longer than we have, and use that
knowledge to good advantage.
When it comes to reproduction orchids are
extremely versatile, but individually selective
and have adapted themselves to use a variety of
pollinators, with or without their consent.
Where many insects are concerned, the plant
attracts them either by smell or mimicry, or in
some instances even a little stealth.
It takes but little imagination to understand
what the orchid on the right "ophrys insectifera"
or as more commonly known the bee orchid is
trying to mimic in order to attract a
pollinator.
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The smell factor is an obvious attraction to a pollinator, but mimicry? well the flowers of many orchids
are so designed to look like either an aggressor of the
pollinator or it sexual partner.
In the case of the Bee
orchids illustrated above, male bees are attracted to the
plants because the flower looks like a receptive female,
and during a frustrating attempt at mating with the
flower, the male bee will become the unwitting carrier
of pollen, which it will duly deposit on its next
amorous flight of fancy.
Some orchids adopt the lure
technique and have long stems the tips of which bear
their flowers, these can dance effectively in the breeze
and look amazingly like butterflies, (Oncidium Papillio).
Many orchid flowers provide an ideal landing platform
for their pollinator to use, this is usually so designed
that in getting to the nectar the insect has to come
into contact with the pollinia of the orchid, and this
will detach itself and stick like superglue to the back
of the unwitting messenger, only to be brushed against
the reproductive organs of its next port of call, in
some instances, the orchid aids the certainty of
securing the pollinia by having a hinge and tilt
mechanism to its lip, this ensures that the insect is
slapped hard against the pollinia as it leans forward
into the flower.
Now we come to stealth, in this case
the slipper orchid lures the insect with a promise of a
drink from its pouch, or attracts it by scent or sight
to the edge of the pouch which is very slippery and
polished, before it knows it the hapless pollinator
finds itself stuck at the bottom, and is either too wet
to fly, or the shape of the pouch precludes it, and
there is only one way out which the insect will
eventually find; as it does escape it will have to crawl
through a small doorway which is so tight that the
pollinator is once again pressed firmly against the
pollinia as it escapes, only to repeat the exercise once
more at another flower, this time depositing the
pollinia as it collects a fresh one, without even
knowing.
Some orchids rely on crawling insects to
pollinate them, and will produce long petals which trail
downwards until they touch the ground or another object,
thus creating a pathway to their flowers.
Orchids really
specialize in their choice of a pollinator, this ensures
the continued purity of the species as the pollinator
can only successfully gain sustenance from its chosen
specie host, take for example the orchid Angreacum
Sesquipidales. Darwin wrote about this one in his origin
of the species, it produces beautiful waxy white star
like flowers, which exude a heavy perfume at night, the
back of the flower has a long spur, sometimes up to 12
inches or so in length, and at the bottom of this spur
can be found a tiny source of nectar. Darwin reasoned
that as the orchid was white, and only fragrant at night
then the pollinator must be a moth, and that to be able
to feed from the orchid the moth must have a tongue at
least 18 inches long.
It was not until
after Darwin’s death that the Predicta Moth was
discovered, which possesses such a long tonge,
unfortunately the great man never had the pleasure of
seeing his theory proven.
Of course, orchids do not rely
on insects alone, humming birds, small mammals, even
bats, and not least of importance the wind, all contribute
to their reproductive successes.
Orchids produce masses
of tiny seeds, one single pod could contain as many as
4million seeds, it would seem obvious that with such a
large harvest, the plants reproduction is assured, but
remarkably orchids do have a major setback when compared
to other forms of plantlife; because the seed is so
small, it does not possess the natural reservoir of food
with which most seeds are endowed, and does not possess
the ability to convert food sources into the useful
sugars etc. which it needs, therefore an amazing
symbiotic relationship forms between the seedling and
certain fungi....... the seed must become infected early in
its life cycle if it is to develop into a mature plant,
and the miccorhizial filaments of the fungus become its
lifeline to the outside world.
The earliest written
evidence of their presence if in the form of Chinese and
Japanese drawing and literature of the circa 700 B.C. At
that time described and used as herbs and cures for many
maladies.
You may be interested to know that the seed
pod of the orchid Vanilla planifolia is used to flavour
ice cream.
World-wide over 35,000 species are known, in
addition there are in the order of 300,000 plus hybrids
registered, these records are kept at Kew here in the
U.K.
In England orchid cultivation commenced some
250-300 years ago as church missionaries, army personnel
and explorers sent plants to friends and patrons. The
nurseries of that era dispatched 'plant hunters' far and
wide. Seafarers also returned with exotic plants to
supplement their income, and it was only natural, (one
of the major ports of the time being Liverpool) that the
North of England became a focal point for orchid
culture.
A few northern names which may strike a chord
with anyone familiar with orchid history are, Thomas
Moss (Cattleya mossiae), a Liverpool Banker; Holbrook
Gaskell (Cattleya gaskelliana) a Liverpool chemical
manufacturer; Enoch Harvey (Dendrobium harveyanum) a
Liverpool solicitor. The Rev John Clowes (Anguloa
clowesii) resided in Manchester, and not too far away in
Staffordshire lived James Bateman (Vanda batemanii).
Whilst in Derbyshire one of the largest collections of
orchids at that time was at Chatsworth, the seat of the
Duke of Devonshire.
Only the then wealthy could afford
the upkeep of 'stove houses' in which to bring back such
plants to growing and flowering condition in addition to
paying the high price orchids would command at auctions
etc.,
Today a mature plant in flower or near flowering
can be purchased from one of the orchid nurseries who
regularly attend our shows for the same cost of the
average florist's bouquet, which usually fades after a
few days, whereas, orchid flowers will last from three
to twelve weeks - some even longer.
Many orchid plants may be kept within the average
centrally heated home to grow happily
and continue to give pleasure with subsequent
flowerings.
Known affectionately as 'The Royal Family of
Plants' orchids grown in a sizeable collection will
challenge the experienced horticulturist, the humble
gardener and the house plant enthusiast as no other
growing experience will; yet there is no mystique since
most orchids can now be cultivated successfully.
The
Author of this site and his wife are both active members
of the Society, and have a mixed collection of orchids
growing happily in their greenhouse, and on the kitchen
windowsill.
It is no longer necessary to have large
greenhouses and even larger pockets to be successful at
growing quality plants.
Providing that the basic rules
of plant culture are followed, anyone who has the desire
can be rewarded by their efforts.
There are approx. 35
wild species in the British Isles - most of which do not
survive being moved from their natural habitat, however
nurseries specializing in "hardy orchids" can provide
similar plants for outdoor growing.
Orchids were on this
Planet long before man arrived, and despite our efforts
to cut back forests, pollute the air and generally
interfere with the ecology of the world as only we can
it is probable that they will be there long after we
have gone.
The theory of some is that it is the insects
which will inherit the earth, then it is likely that the
insects will unwittingly help to prolong the orchids
success as a survivor, perhaps it is the orchids who
will really inherit the earth !.
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