The colours of autumn are a spectacular sight in the UK, and this year's Indian summer may mean it is even more striking
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When is a leaf not a leaf? When it's an autumn leaf. To the untrained eye, leaves may not be a particularly awe-inspiring subject, but as the season turns to that of "mists and mellow fruitfulness", they become a thing of beauty and wonder.
Leaves are also one of Mother Nature's most delicate and complex creations. If you pause for a second and think of the many colours, shapes and textures around us, they are all the product of specific and unique chemical reactions that take place within.
Here at the Woodland Trust, we believe that this autumn has the potential to be one of the most colourful for many a year, with the current Indian summer we are experiencing potentially providing a spectacular display of autumn colour.
For the uninitiated, a quick pr�cis of the science behind changes in leaf colour. During photosynthesis, leaves have to produce chlorophyll to capture the energy from the sun, and it is this chlorophyll that gives them their green colour. As summer turns to autumn, the photosynthetic process slows down as the days get both shorter and colder, which in turn leads to less chlorophyll production and the green fading to yellow. The yellow is carotene, which is hidden during spring and summer as the leaves are at their peak of chlorophyll production.
As for the reds, golds and purples, this is anthocyanin at work; a pigment produced as a result of a complex reaction between proteins and sugars in the leaf. This only occurs in particularly warm and sunny weather. Combine this with cool but not freezing nights, which help destroy the chlorophyll and enhance anthocyanin production, and this will hopefully lead to the vivid red and purple hues we all enjoy so much.
So there really is no excuse not to get out ? whether into the back garden, the local park or to the woods ? as you're not going to get a better display of colour all year. There are thousands of woods to visit, from young woodland on rolling plains like Heartwood Forest near St Albans, where the saplings are just peeping out of the ground, to deep, dark, mysterious ancient woods like Savernake Forest in Wiltshire. Every single one has a character of its own.
Furthermore, whilst out taking your arty snaps, you can also indulge in a little of what we call 'citizen science' by taking part in the Woodland Trust's Nature's Calendar project. When out and about, make a note of what you see, and record the dates. This could be the leaves turning from green to yellow or red, the leaves falling to the ground, or the first signs of holly berries. We compile thousands of such records every year and with the information recorded we're able to see what is happening in the natural world around us.
For example, from 40,000 individual pieces of data recorded this spring we were able to discern that spring 2011 was the earliest arriving this century. As an added bonus, you can also get printable ID guides and fact sheets to help you identify what you see ? along with the odd hedgerow tipple recipe.
? Beverley Gormley is Nature's Calendar project manager
Source: http://www.guardian.co.uk/environment/blog/2011/sep/30/autumn-colours-green-shoots-photographs
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