Hazel

This is a Hazel (Corylus avellana) bush during a summer shower.

 

Now leaves should be falling, but this year they don't fall that much. To turn yellow or red and to detach themselves from the branches, they need some cold days or nights. Well, this autumn is too warm, so there is still a lot of green in the forest.




Those Hazel leaves, oval shaped, dented, with visible veins and a typical little point at the end, got paler, but just a little bit.




There are individual differences between bushes, all the same. Under a Hazel a bit further on there are already a lot of fallen leaves.

In some weeks there will be nothing but naked boughs.





An old Hazel bush looks like a big bunch of trunks and branches that come out of the ground at roughly the same spot; when the oldest of them die, new shoots develop near them.

Hornbeam

Some fallen leaves in a Hornbeam wood.




But normally leaves of Hornbeams (Carpinus betulus) turn yellow in autumn, isn't it? It seems this is not always true.




Confirmed when we look upwards. Two Hornbeam trees wit reddish leaves. Exceptions to the rule exist.

Tree Lungwort

On a tree trunk grow salad-green leave-like structures. At least, in this wet autimn they are clear gree, when it is dry they will turn brownish. They are from a lichens called Tree Lungwort (Lobaria pulmonaria), one of the biggest lichens of France.





Its thallus (the "leaf"), a long, lobed shape more or less hanging can get until 40 cm long. Here, the thalli are much shorter. If you look from nearby you see the thalli have different colours and shapes.





The lichen is a slow grower, and there are younger and older thallu present on the same tree.





Their surface is reticulated and on the ridges grow little soredia, here visible as a kind of grey-green powdery stuff. Soredia assume the vegetative reproduction of the lichen, they contain samples of the ascomycete and the cyanobacter that live together as a lichen, and that can move on towards another tree.






Tree Lungwort is an organism of older forests with old deciduous trees, in Dordogne Oaks and Hornbeams. Because it is sensitive to certain kinds of air polution, notably sulfur dioxide, it has disappeared from industrialized and urbanized areas. In Périgord it can still be found, here and there.