Found: 390 million year old forest

Rather than solid wood, their trunks were thin and hollow in the centre. They also lacked leaves, and their branches were covered in hundreds of twig-like structures.

These trees were also much shorter than their descendants: the largest were between two and four metres tall. As the trees grew, they shed their branches, dropping lots of vegetation litter, which supported invertebrates on the forest floor.
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“This was a pretty weird forest – not like any forest you would see today,” said Davies. “There wasn’t any undergrowth to speak of and grass hadn’t yet appeared, but there were lots of twigs dropped by these densely-packed trees, which had a big effect on the landscape.”