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There
are more species of Orchids than any other
plant group on Earth. In numbers of
individual plants though, grasses would be
more numerous.
Orchids are
found from the equator to much colder
latitudes. They are abundant in Northern
Asia and North America, many islands and
in the Southern hemisphere as well. Those
in colder areas are primarily terrestrial
and many in warmer climates are epiphytes.
Alaska has thirty one species that are all
terrestrial. They go by names such as
Moccasin Flower, Bog Orchid, Ladies
Tresses, Calypso, Ladies Slipper, Twyblade
and Rhizome Orchis (Orchis is a genus of
some tropical species). None of the Genus
Orchis is found in Alaska.
In tropical
places Orchids range from extremely small
flowered forms, a few mm wide, to five
inch giants. Central America has many that
are epiphytes and will grow on anything
they can get a firm hold on. They are
found on tree limbs and trunks, telephone
wires, rock walls and on some on woody
vines. Epiphytes are not parasites. They
obtain all of their nutrition from the
air. Needless to say, they grow where
there is very high humidity.
Vanilla is
obtained from the seed pods of an Orchid
that is similar to the one in the
illustration to the right.
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Above,
the beautiful Black
Orchid, national flower of
Belize
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When talking
about Orchids we must think about them
first as a group. As stated above, there
are more species of Orchids than any other
group of flowering plants. There are
35,000 species of known orchids. Most
species are found in tropical areas but
many others are indigenous to the far
northern and Southern hemispheres. Those
found in more hostile cold environments
are usually terrestrial. They vary greatly
in habitats, size and
flower.
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A typical epiphytic orchid from
tropical environments.
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The smallest
is found in South America and has a flower
only one half millimeter in diameter and
the largest, found in Madagascar (Malagasy
Republic), reaches a diameter of over
eighteen inches. One species is so
delicate that the flower lasts only a few
minutes after blooming.
The largest
orchid plant is found growing in large
jungle trees in Malaysia and the
Philippines. It produces about ten
thousand flowers and weighs up to two
tons. Many species are epiphytic attaching
to tree bark, wires etc. They are not
parasites, having no roots, only
hold-fasts, as lichens or seaweeds do.
There are aquatic tropical forms, and in
Australia (of course) there is a
saprophytic species (Rhizanthella
gardeneri) living and flowering completely
underground, feeding from the roots of
larger terrestrial plants. One genus of
orchids that is known by all is Vanilla
spp. which grows pods (not beans) that
produce the well known
flavoring.
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A tropical orchid that is
terrestrial.
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Orchids have
three petals subtended by three sepals.
One petal is usually drooped and called
the lip. The stamens and pistil are
combined into a single structure and is
referred to as the column which is found
only in the Orchidaceæ. The stigma,
on top of the pistil, often consists of a
sticky depression, and the pollen bearing
anthers are covered with a cap that is
removed by an insect crawling over
it.
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Nowhere else
in the world of plants are so many species
dependent upon insects for pollination.
Many orchid flowers so perfectly mimic a
female insect of the pollinating species,
that males are attracted to it, even
people are fooled by it. One entomologist
in South America was shocked seeing he had
netted some orchid flowers thinking they
were insects.
Orchids have
very small seeds and some species have
over a million minute seeds from a single
flower. Growing them in greenhouses from
seed can be very frustrating. Now the
orchid growers meri-clone and tissue
culture orchids in the lab.
In Alaska I
had fair luck collecting ripened seed pods
an sprinkling them in proper habitat. I
imagine the germination is at a ratio of
perhaps five million to one. Even then
they don't seem to spread or return very
well. There are a large number of orchids
in Alaska but they are all terrestrial.
Many are perennials and those that aren't
usually re-seed well enough that their
numbers remain rather constant.
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Below
are some boreal orchids found
Alaska:
Pink
Lady Slipper - Lady Slippers and
Moccasin Flower Orchids occur in Alaska,
but they are rare on the Kenai Peninsula.
They are quite common from Anchorage and
north.
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Round
leafed orchid - A beautiful small
orchid found in the interior.
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Rose-purple
Orchid - This species is common along
the Aleutian Range and has been brought
into Seward and Homer where it has
escaped.
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Frog
Orchid - Look for this species in damp
areas where there is little competition
from larger plants and has lots of
sunlight.
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Large
Bog Orchid - Can reach a height of
five feet. Found in wet areas, prefers
clearings in alders along south facing
hillsides.
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Rattlesnake
Plantain Orchid - This species is
common in mixed woods and climax spruce
forests. It grows in mossy areas. Look for
the leaves.
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Twyblade
Orchid - Perfectly names, it has two
leaves and the flowers are greenish or
purple. It is common in our
forests.
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Coral
Root Orchid - Without leaves, it
photosynthesizes through the stem. Don't
dig it up to see the strange coral-like
root.
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Calypso
Orchid - This is an outstanding
species. It has been found on the Kenai
Wildlife Refuge, near Homer and Seward.
It reported from the Hope Area. It can
be found more abundantly north of
Anchorage in mixed woods.
-End
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