Lycopodium dendroideum is a clubmoss native to the northeastern USA. It is part of a complex of species colloquially known as groundpine, which taxa were formerly lumped into the species Lycopodium obscurum. 
L. dendroideum prefers humus-rich, sandy, moist but not completely saturated soils.
This and other Lycopodium species have been commonly collected for decorative Christmas greenery. The spore of this species was also collected as Lycopodium powder for use in early photography, although this was not the preferred species for the purpose.