Lycopodium clavatum

Lycopodium clavatum (Stag's-horn Clubmoss or Ground Pine) is the most widespread species in the genus Lycopodium of the clubmoss family Lycopodiaceae.

It is a spore-bearing vascular plant, growing mainly prostrate along the ground with stems up to 1 m long; the stems are much branched, and densely clothed with small spirally-arranged leaves. The leaves are 3-5 mm long and 0.7-1 mm broad, tapered to a fine hair-like white point. The branches bearing spore cones turn erect, reaching 5-15 cm above ground, and have fewer leaves than the horizontal branches. The spore cones are yellow-green, 2-3 cm long and 5 mm broad. The horizontal stems produce roots at frequent intervals along their length, allowing the stem to grow indefinitely along the ground. The stems superficially resemble small seedlings of coniferous trees, though it is not related to these.

It has a subcosmopolitan distribution, with distinct subspecies and varieties in different parts of its range:
 * Lycopodium clavatum subsp. clavatum
 * Lycopodium clavatum subsp. clavatum var. clavatum (Europe, Asia, North America)
 * Lycopodium clavatum subsp. clavatum var. aristatum (Mexico, Caribbean, Central America, northern South America south to northern Argentina)
 * Lycopodium clavatum subsp. clavatum var. asiaticum (Japan, northeast China)
 * Lycopodium clavatum subsp. clavatum var. borbonicum (central and southern Africa)
 * Lycopodium clavatum subsp. clavatum var. kiboanum (mountains of tropical Africa)
 * Lycopodium clavatum subsp. contiguum (southern Central America, northern South America; syn. Lycopodium contiguum)

Although globally widespread, like many clubmosses, it is confined to undisturbed sites, disappearing from farmed areas and sites with regular burning. As a result, it is endangered in many areas.

Common clubmoss, Stagshorn clubmoss, Wolfpaw clubmoss, Foxtail clubmoss, Running clubmoss, Running ground-pine, Running pine, Running moss, and others.
 * Other common names

The spores of this moss, "Lycopodium powder", are explosive if present in the air in high enough densities. They were used as flash powder in early photography.
 * Use