01/30/2021
Ground-pine (Dendrolycopodium obscurum) and running cedar (Diphasiastrum digitatum) are in the same family, look very similar, can occupy similar habitats, and are found commonly throughout the state.
Reminding our readers that these should NOT be collected. Although they may be abundant in areas where they grow, habitat reduction has indeed reduced substantially the total population. Also, they are EXTREMELY flammable.
The branches of running cedar are narrower than that of ground-pine, and the leaves are in four ranks as opposed to six. Additionally, whereas the strobilus (the spore-bearing structure) appears to have a main axis in ground-pine, it branches dichotomously in running-cedar. Both ground-pine and running cedar spread through an extensive rhizome system that typically grows unidirectionally. Each year at the beginning of the growing season, the rhizome grows a few centimeters and forms a branch at a 90 degree angle, alternating branching sides each year. Every year, the main rhizome only produces one new aerial root. Running cedar can be found in “Mesic to, less often, dry acidic forests, old fields, and clearings; especially common in formerly disturbed soils under successional pine and Tulip-tree forests” according to the Digital Atlas of the Virginia Flora.
Pictures are courtesy of the Digital Atlas of the Virginia Flora.