Plantwatch: Dazzling leaf colours brewed over a long autumn

It’s been an extraordinary autumn. Despite the battering from wind and rain in October and November, the leaves of many trees are still hanging on. It has really only been this week that most of the country has had cold frosty  nights. The chill will help shed the rest of the leaves.

The autumn has lasted so long that the Woodland Trust has reported 2014 to have been one of the few years when there was enough time for leaves to develop a full tint of some of the more spectacular of the autumn colours – such as the red splash of the field maples, the only native maple in Britain.

Especially good leaf colours have appeared on the edge of woodlands where the trees and shrubs were exposed to more sunshine.

But with lots of grey skies this month, many of the trees’ colours did not have much chance to shine brightly.

What is clear is how autumn now, year by year, is being pushed back later and later over the year.

Key to this change in the seasons is the trend for increasing temperatures, but rising levels of carbon dioxide may also be playing a part in delaying the autumn colours. Not only does carbon dioxide help drive climate change, but studies also suggest that CO₂ is helping to keep leaves greener for longer.

All of which raises the interesting question – what is going to happen to autumn in the future?

As the season comes later, and as spring starts earlier, the winters are getting squeezed and not leaving much time for trees to lie dormant.