Tuesday 26 September 2017

Golden age for detoxing trees

AT his door, the leaves were falling but Johnny Cash never got over those blue eyes. Walter Huston, legendary actor and Angelica's grandfather, croaked about the autumn weather turning the leaves to flame/"And I haven't got time for the waiting game". (Maxwell Anderson wrote the lyrics; Kurt Weill the melody). Ah yes, all the romance and memory of the Fall of the year.

An anthropologist and poet named Loren Eisley asked that if men could disintegrate like autumn leaves, would not our attitude to death be different? Just suppose we saw ourselves burning like maples in a golden autumn. It's a thought.

The English naturalist Richard Mabey says we all find auguries in the blaze of autumn -- prophesies of winter, reminders of our own mortality, or, like John Keats, some comfort in mellow fruitfulness.

But why do trees change the colour of their leaves only to eventually dump them?

We like to think it occurs so that they can endure. But we don't really know.

Just why temperate trees shed their leaves still isn't fully understood. It may be partly because the roots don't easily absorb cold water and need to reduce moisture lost through leaves and partly also to get rid of toxins.

But what happens before the great shedding is a transfer of sugars and nutrients back into the branches for storage. What is left after the chlorophyll has gone are the natural antioxidants, yellow and orange carotenoids and another protector, the tomato-red anthocyanin, specially appearing for the autumn.

The season's high colour then is not a sign of deterioration but of detox vitality. Keats found something uplifting about it at a bad time in his short life (To Autumn, 1819 when he was dying of TB).

Autumn is not about decay at all but about ripening and preparing for the new beginning of next spring.

George Orwell puts the tomato simile into Keep the Aspidistra Flying. When the

man and woman are in the woods and she is up to her knees in leaves, she cries: "Look at them with the sun on them. They're gold." He responds: "Fairy gold ... They're just the colour of tomato soup."

The ripening of tomatoes, fruits of the sun and source of antioxidants, may be analogous to what happens to leaves at this time of year.

All plants have to survive winter, as indeed do all of us! Annuals disappear and survive as seeds. Perennials keep their buds near or in the ground. But a tree has to have its buds up high so that new leaves can grow each spring.

The annual tints have been appearing earlier, led by the beeches, sycamores and hazels. The ash is the first to shed its protective mantle, the last to replace it in the spring.

Earlier colour change was supposed to be an indication of a glorious summer in the year ahead but the opposite has occurred. Perhaps the tree roots have been stressed out with too much water, as indeed have us unfortunates who live beneath them!

Sunday Independent

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