What it is
A horsetail the size of a tree. Its relatives alive today grow knee-high in damp ground. This one, called Arthropitys, grew a jointed trunk of real wood and a crown of branches, at least three orders deep. One trunk found at Chemnitz is estimated to have stood at least 15 meters tall, about fifty feet.
Leftovers in the pith
Its stems had a hollow core. In the core of one fossil branch, scientists found tiny droppings, a few millimeters long, packed with bits of the plant's own wood. Something was living inside the tree and eating it. From the size of the droppings, the team tentatively suggests a kind of millipede.
Rings and scars
Its trunk laid down growth rings, crowded most densely near the outside. The team reads them as a record of a changing climate and of volcanic upsets coming harder and more often, until the last one buried the forest. Another calamite from Chemnitz shows such severe damage in its wood that it may be the trace of a lightning strike. The paper on it ends its own title with a question mark.
Read the sources
- The largest calamite and its growth architecture: Arthropitys bistriata from the Early Permian Petrified Forest of Chemnitz · Review of Palaeobotany and Palynology (2012)
- When horsetails became giants · Chinese Science Bulletin (2012)
- Severe growth disturbances in an early Permian calamitalean: traces of a lightning strike? · Palaeontographica Abteilung B (2018)
- A snapshot of an early Permian ecosystem preserved by explosive volcanism: new results from the Chemnitz Petrified Forest · Palaios (2012)