Description
Stomata and epidermal phytoliths.
Stomata and epidermal cells are diagnostic at the genus level (Equisetum). Epidermal cells feature "granulate surfaces and elevated projections along the edges" (Morris et al. 2009: 346; Piperno 2006).
Supporting literature:
Piperno, D.R. 2006. Phytoliths: A comprehensive guide for archaeologists and paleoecologists. AltaMira Press. pg 190.
Morris, L.R., Baker, F.A., Morris, C., and Ryel, R.J. 2009. Phytolith types and type-frequencies in native and introduced species of the sagebrush steppe and pinyon-juniper woodlands of the Great Basin, USA. Review of Palaeobotany and Palynology 157: 339–357.