Section of fossil tree fern *Tempskya wesselli* from the Cretaceous of Idaho. *Tempskya* is in an extinct family of ferns, Tempskyaceae. Ferns cannot produce true wood. Instead, the “trunk” of *Tempskya* consists of multiple narrow stems (visible as circles on one face of this specimen) surrounded by roots. This specimen is from the paleobotanical collections of the School of Integrative Plant Sciences at Cornell University, Ithaca, New York. Longest dimension of specimen is approximately 8.5 cm. Model by Emily Hauf.