These fossils, found along sandstone cliffs in southwest England, provide a rare window into the Devonian period, when the first land animals appeared and plants began to reproduce by seed.

proto-trees

The ancient forest consisted of Calamophyton trees, resembling 13-foot giant thistles, with multi-sprout hollow trunks. These strange structures grew until they broke apart; This intrigued researchers and significantly differentiated them from modern forests.

Fossils of the planet’s oldest forests / Photo CAMBRIDGE

The dense arrangement of these trees left a significant mark on the landscape. Lacking understory or grass, Calamophyton’s fallen branches contributed to sediment deposition, affecting the flow of ancient rivers and altering the interaction between water and land.

It was a very strange forest, unlike any forest you see today. There was no undergrowth to speak of and the grass had not yet appeared, but there were many branches falling from under these dense trees, making a huge impact on the landscape.
– said Neil Davis, professor of Earth Sciences at the University of Cambridge and first author of the paper.

Devonian window

This discovery not only sheds light on the characteristics of the oldest forests, but also their role in shaping Earth’s geological and ecological history. Because the Devonian Period was so important to life on Earth, understanding these forests helps us understand the fundamental changes that occurred during this period.