New York Natural Heritage Program
Appalachian Firmoss
Huperzia appressa (Desv.) A. L?ve & D. L?ve
Clubmosses

General Description [-]
Appalachian Firmoss is not a true moss as the common name implies. It is an evergreen, non-flowering vascular plant (or tracheophyte, reproducing by means of spores rather than seeds). Its stems occur in tufts and branch from the bases or from further up the stem. The stems are 6-10 cm tall and live for about 12-15 years before dying. The green to yellow-green leaves occur singly along the stems and are 2-6 mm long. The spore producing structures (sporagnia) are yellow, and occur in zones along the stems in the axils of the leaves. Asexual propagules, known as gemmae, are produced throughout the upper portion of the stems. These gemmae fall from the plants and start new individuals (Beitel and Mickel 1992, Wagner and Beitel 1993, Haines 2003).

Best Life Stage for Proper Identification [-]
Mature spores are needed to confidently distinguish this species from other closely related taxa including hybrids.

Similar Species [-]
Huperzia selago is superficially similar although it does not grow in alpine settings. It can be distinguished by having gemmae produced in distinct single whorls at the apex of annual growth, lateral lobes (leaves) of gemmae 1.5-2.0 mm wide, and leaves from the upper and lower portions of the stems relatively more similar in length and orientation. Also, the shoots do not senesce, turn yellow, and die with age.

Huperzia lucidula is also superficially similar, but again does not grow in alpine settings and instead prefers cool moist forested habitat. It can be distinguished by its toothed leaves, widest above the middle, and by having stomates only on the abaxial surfaces. The gemmae are produced in distinct single whorls at the apex of annual growth, the lateral lobes (leaves) of gemmae are 1.5-2.5 mm wide, leaves from the upper and lower portions of the stems are relatively more similar in length and orientation, and obvious winter bud constrictions are present (represented by narrow zones of short ascending leaves). Also the shoots do not senesce, turn yellow, and die with age.

Huperzia x josephbeitellii, the hybrid between H. appressa and H. selago is similar to and is often found in the same alpine habitats as H. appressa. The hybrid is very similar to H. appressa plants that grow in the shade. Therefore, all specimens of H. appressa should be carefully compared to this hybrid. Huperzia x josephbeitellii can be distinguished by the production of abortive spores. Abortive spores are spores which are sunken or mis-shapen and have less luster than non-abortive spores. In the hybrid about 25-50% of the spores are abortive. Immature and spores from a previous season may appear abortive. Therefore, spores should only be assessed from plants late in their growing season (mid-August through October in New York). Huperzia x josephbeitellii is similar to H. appressa in that the gemmae are produced throughout the upper portions of the stems and leaves from the upper and lower portions of the stems are dis-similar in size and orientation. Characters that distinguish the hybrid from H. appressa are that the hybrid plants are more robust with the upper portions of the stems 7-10 mm wide (incuding the leaves) and the lateral lobes (leaves) of the gemmae are 1.1-1.5(-1.7) mm wide.
Appalachian Firmoss Images
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The Best Time to See
This species starts to have mature spores in late August and these remain in good shape through October. Therefore, since spore morphology is important in distinguishing this species from similar taxa, the best time to survey for this species is during this time period.
J F M A M J J A S O N D
Vegetative Fruiting
The time of year you would expect to find Appalachian Firmoss vegetative (blue shading) and fruiting (orange shading) in New York.