Earliest Forest in the World in Devon and Somerset

A correspondent sent me the link to THIS ARTICLE, for which I am very grateful. The article is based on THIS PAPER. The papers concern newly discovered fossil trees found in Middle Devonian sandstones in the Hangman Sandstone Formation which is of Eifelian age (393 - 387 million years).

Not only were fossilised trees found but also forests. The trees are of an extinct species related to ferns and horsetails - the cladoxylopsids, which look rather like palm trees - long stem (2 - 4m) with "leaves" like palm fronds at the top. (Here "leaves" means lots of twiglets.)

There are older trees to be found but this is the oldest forest. And it marks the time when vegetation had a significant impact on sedimentation, changing the way the non-marine surface of the earth looked. 

The Hangman Sandstone Formation

The tree trunks are preserved mostly as impressions. The most abundant forms show a three-dimensional surface, consisting of longitudinal strips of slightly raised smooth matrix alternating with slightly lower relief strips in which short transverse depressions are closely arranged (A - D). (See pages 12 and 13 of the academic paper)