Key to the Common Lycopodiaceae of Western Washington These herbaceous plants have small, needle-like evergreen leaves that usually are spirally arranged or alternate on the stem, or occur in opposite pairs. Depending on the species, the stems may: 1) be long creeping and horizontal with erect branches, 2) occur in clusters and be forked, or 3) occur as a single branch that arises from a rhizome (horizontal stem in substrate). The sporangia are produced in distinct terminal strobili (cones) or occur in the axils of leaves and not forming a distinct cone. 1a. Sporangia occurring in the axils of green leaves (looks like normal leaves) along the upper stem and not in a well-defined strobilus (cone). Branches erect with equal dichotomies (forking).................................... Huperzia occidentalis 1b. Sporangia occurring in well defined, terminal cones............................................................... 2 2a. rhizome horizontal, producing erect, unbranched, stem with terminal cone, leaves of cone similar to normal green leaves.................................................................................. Lycopodium inundata 2b. Sterile branches erect or ascending, cones with yellowish, scale-like leaves, very different from normal green leaves.................................................................................. 3 3a. Cones sessile (at the tip of leafy stems)................................................................................... 4 3b. Two cones on long stalk-like stem that are not leafy (may have small scale-like leaves)........................................................................................... 7 4a. Aerial stems erect, forking or branching many times. Each stem tree-like in appearance ..................................................... Lycopodium dendroideum 4b. Aerial stems in clusters or tufts, bushy, or fan-like ................................................................ 5 5a. Aerial stems erect and unbranched. Leaves rigid, sharply-pointed, glossy, and uniform in size along branches.......................................... Lycopodium annotinum 5b. Foliage waxy and sometime cedar-like, with aerial stems often fan-like, shorter than 12-13 cm, leaves in 4-5 rows, scale-like, partially fused to the stem .................. 6 6a. Sterile branchlets rounded and waxy, leaves short and appressed (stem-hugging). Rhizone / runners sometimes yellow and leafless (subterranean) .…............................................................ Diphasiastrum sitchense 6b. Sterile branchlets flattened, plant typically small and compressed in stature with waxy glaucous (bluish) foliage ..………..................……..Diphasiastum alpinum 7a. Leaves narrow, awl-shaped with long hair-like tips. Rhizomes/runners and staghorn-like side branches covered in dense helices of bright yellow-green, hair-tipped leaves........................Lycopodium clavatum 7b. Leaves highly reduced, opposite in orientation and nearly completely fused to flattened branches, waxy foliage closely resembling that of cedar, branches umbrella-like with an erect main branch dividing into radiating flattened branchlets at the top ………................…… Diphasiastrum complanatum .