Lycopodium alpinum is a species of clubmoss

Lycopodiopsida

Lycopodiopsida is a class of plants often loosely grouped as the fern allies. Traditionally the group included not only the clubmosses and firmosses, but also the spikemosses and the quillworts...

 known by the common name alpine clubmoss. It has a circumboreal distribution, occurring throughout northern latitude

Latitude

In geography, the latitude of a location on the Earth is the angular distance of that location south or north of the Equator. The latitude is an angle, and is usually measured in degrees . The equator has a latitude of 0°, the North pole has a latitude of 90° north , and the South pole has a...

s in the Northern Hemisphere. It is an indicator

Indicator species

An indicator species is any biological species that defines a trait or characteristic of the environment. For example, a species may delineate an ecoregion or indicate an environmental condition such as a disease outbreak, pollution, species competition or climate change...

 of alpine tundra

Alpine tundra

Alpine tundra is a natural region that does not contain trees because it is at high altitude. Alpine tundra is distinguished from arctic tundra, because alpine soils are generally better drained than arctic soils...

 and boreal climates

Subarctic climate

The subarctic climate is a climate characterized by long, usually very cold winters, and short, cool to mild summers. It is found on large landmasses, away from the moderating effects of an ocean, generally at latitudes from 50° to 70°N poleward of the humid continental climates...

.

This plant grows 10 to 20 centimeters tall from stems which grow just under the surface of the ground. The leaves are hollow at the bases. The female stems produce strobili

Strobilus

A strobilus is a structure present on many land plant species consisting of sporangia-bearing structures densely aggregated along a stem. Strobili are often called cones, but many botanists restrict the use of the term cone to the woody seed strobili of conifers...

 up to 3 centimeters long.

This species may hybridize with Lycopodium sitchense.