yellow

it seems this is a yellow autumn. though the leaves are only just starting to turn, so perhaps it’s yellow then orange and rust. we hardly get red leaves in England, although the dogwoods are turning deep maroon, and I saw a guelder rose still with its red berries and darker red leaves today.

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today was clear and blue. autumn sunshine is warm and yellow, because the sun is lower in the sky.

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red pigment in plants is caused by the anti-oxidant anthocyanin, which seems to be a response to stress. when trees shut down for the winter they withdraw the green pigment chlorophyll back to store for the next year, which opens the leaf to attack by oxygen radicals, and anthocyanin prevents this. yellow pigment is carotene, which seems just to be left behind after the tree has stripped its leaves of chlorophyll. so a less stressful autumn produces less reds and oranges in the leaves. (this information I gleaned from Colin Tudge’s The Secret Life of Trees, a wonderful collection of facts about trees.)

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this is a field maple, our only native maple tree. its quite a big specimen and its leaves have turned colour rather early. it has a little bit of orange, but mostly the leaves have just turned yellow. field maple leaves do often have a good deal of red.

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the bracken has turned bright yellow in places too.

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very pretty, but I think it is just a halfway stage, eventually progressing to rusty russets.

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