Autumn colour mystery

In the misty moisty days of November, there is still a lot of colour in the wild.  This is a patch of blackthorn. The yellow leaves contrast strikingly with the rusty brown oak leaves and the silhouettes of the trees behind.

 

 

 

But here's a strange thing:  in the misty photo above, the blackthorn on the right has yellow leaves, while on the left the leaves are green with a tinge of brown.  The same plant but completely different colours.  And so too with the brambles.

 

 

Some of them are bronzy red while others are still green and growing.