Today's horsetail plants are living fossils, the only surviving members of the class Equisetopsida. For more than a 100 million years, Equisetopsida plants dominated the understory of the late Mesozoic period forests, stretching up to 30 metres high. (From the American Journal of Botany, on the Short Sharp Science website.)
Twice I posted Marlin's great photograph with more text and images of fossil horsetails, and each time it just disappeared. This time I'm taking it in two parts. Here are today's horsetails, which I've loved since childhood, and some images of the fossil record in the next post. Hope it takes.