The spectacular event of green leaves turning to reds and yellows in October and into November happens when trees have taken all the nourriture they can from the leaves that are filled with chlorophyll, the biomolecule that absorbs energy from sunlight and gives leaves their green colour.
When sunlight wanes, and leaves stop making nourishment, this green pigment is broken down into opposing colour compounds. Yellow pigments are then revealed and other chemical changes cause red coloration.

Biologically, the reason why green leaves turn to hues of reds and golds in the autumn season, is when trees have depleted all the nouriture obtained by chlorophyll. Chlorophyll is necessary for photosynthesis, allowing green leaves to absorb energy from light. Green leaves convert carbon dioxide and water into oxygen and glucose.

Although artists and poets might be aware of this biological process, they regard the glorious colour change more philosophically, or they might relate it to the theory of colour.

I have often referred to colour polarity, and polarity in general, as I find it a fascinating subject. Depending on the tree, of course, the particular green of its leaves, the colour change process seems to reach its splendid culmination when the hue of red becomes the exact opposite of the original hue of green.

A green leaf that tends towards yellow might change to a reddish gold, and a green that tends towards turquoise might change to a warm silver tint. But then the richness and variety of autumn colours defy such theorising.

The philosophical aspect is of course the fabulous crescendo of colour that heralds the cycle of life and death. Polarity. The leaves fall, or are carried off by the wind. They become brittle, then sodden and colourless. The earth reclaims them.
When leaves like those of maple or sycamore become brittle, breaking away leaving only the graceful, skeletal veins like fine lace, one always admires such exquisite, intricate, geometrical beauty.

Each year we see this, and are always enchanted, as we also are by the magic of spring. Or certainly we should be. Naturally the seasonal shows are not always the same each year, but then this enhances the wonder and beauty of natural evolution.

Autumn reminds us of the ephemerality of life. It always evokes nostalgia and reflection. But it also reassures. Whatever soothsayers claim to predict, more intent on prophesying dismal doom than paying heed to such sublime, fleeting gifts, seasons continue their cycles. Each year they graciously and poetically reveal divine, timeless truth.

 Text and images © Mirino. November, 2019

1 comment:

Mirino said...

None of these photographs have been enhanced by any additional saturation. The colour crescendo lasted less than two weeks.