Why we get autumn colours...

Hi Everyone!!

 

I have seen many awesome autumn photos so far on flickr, well done to you all!!

 

How many of you actually know WHY we get autumn colours?? If you don’t know then read on!!

 

In autumn the leaves of deciduous trees respond to the colder weather and reduced sunlight by creating a barrier of special corky cells where the leaf stem joins the twig. This seals the leaf off from the tree’s circulatory system. The chlorophyll, which is the substance which makes leaves green and is also is the catalyst in the process of photosynthesis, starts to break down which fades the green colour in the leaves and allows the other pigments in the leaf, which had been present all along but were dominated by the green chlorophyll, may show through as beautiful autumn colours before the leaf falls off the tree!!

 

So basically there are many colours always present in a leaf but because the chlorophyll is the main substance in a leaf then that will always be the dominant colour until the stem of the leaf gets blocked off and the chlorophyll starts to fade!!

 

I have chosen this photo as it displays nearly the whole process described above!! I have added some notes to describe the various stages!!

 

I hope that my explanation was easy to understand and that it sheds a bit more light on why we have autumn colours!!

 

Have a great Sunday my friends!!

David!!

 

Done