[5] Similar to other members of the genus, the sporophyte of Dendrolycopodium hickeyi resembles the seedlings of some conifers.

The upright sporophytes grow from subterranean horizontal stems, often causing tree club-mosses to be found in clusters.

[6] These plants remain green throughout the winter and in their final year, they produce usually a single, unstalked (sessile) terminal strobilus from which spores are released.

[9][10][15] In elevating the plants from varietal level to species level, Wagner et al. opted to forgo the common (but not mandatory) custom of using the old varietal epithet as the new species epithet since D. hickeyi and D. dendroideum both have leaves of equal length around the branches.

They chose instead the name Lycopodium hickeyi in honor of the pteridologist James Hickey who originally described the plant as L. obscurum var.