Saturday 18 June 2016

The orchids of Radley Lakes

It is somewhat surprising that Radley Lakes does not feature more often in this blog.
A collection of lakes formed by quarrying has produced a wildlife oasis in North East Abingdon: where otters can occasionally be seen swimming in the lakes; hobbies feeding on the abundant dragonflies; barn owls quartering over the nearby meadows and even the occasional migratory osprey stopping off as it heads to Africa for the winter.

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Not only are the lakes are a magnet for wildlife, but the poor quality soil means it is ideal habitat for some of our most impressive flowers - orchids.
The most obvious are the clumps of common spotted orchids.
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Elsewhere, the pyramidal orchids are starting to flower.
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Probably the most impressive of the local orchids is also the most difficult to find. The flowers of a bee orchid are less than 1 cm wide and occur in small groups.
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The distinctive flower has evolved for pseudocopulation - achieving pollination through emulating a female insect which attracts a male,  which tries to copulate with the flower, resulting in a frustrated male and a pollinated flower.
Unfortunately for the bee orchids at Radley Lakes, the bee it attempts to mimic is extinct in the UK and hence it relies on self-pollination to reproduce.
The resultant seeds are microscopic and can be blown for hundreds of miles to try and find suitable habitat, where not only will it try to find an insect to help spread it genes, but also a symbiotic fungus; its seeds are so small they do not have any food for the early stages of growth, and so extract it from the fungus.
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Whilst the orchids are impressive, they can be as elusive as the otters, owls and osprey, it is a more common plant which is probably the most attractive. The low nutrient soil restricts the growth of dominant grasses, with the result of thousands of ox-eye daisies turning a disused quarry into a fantastic vista.
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