The Carlisle Mosquito Online

Friday, December 14, 2007


Kay Fairweather reports that she "persuaded the Lycopodium to arrange itelf as a menorah" in honor of Hanukkah. (Photo by Kay Fairweather)

Biodiversity Corner


I have covered various species of Clubmoss or Lycopodium in this column before, but last weekend mid-way through Hanukkah, I noticed fruiting bodies of Lycopodium obscurum protruding through the snow along the Acorn Trail and the Tophet Trail in Great Brook Farm State Park. Not one of them was like a podium but many were like candelabra and with some manipulation I persuaded them to form menorahs.

Classification. Clubmosses are classified along with ferns in a group called Pteridophytes. They are not actually mosses. Like ferns, they have spores rather than flowers and seeds. Also like ferns, they are vascular plants having phloem and xylem to transport food and water and give them structural support so they can grow taller than non-vascular plants.

Name. The genus name, Lycopodium, is derived from the Greek lukos (meaning wolf) and podos (meaning foot) but you will need some imagination to see any resemblance to a wolf's foot. The species name, obscurum, is from the Latin and means dark, shady, or obscured. This is easier to understand since they grow in dark shady habitats. Clubmosses have other common names including ground pine, princess pine and running pine. This one in particular looks very much like a tiny evergreen tree.

Cones. Clubmosses bear spores on "cones" or fruiting bodies called strobili. In some species, the strobili stand high above the leaves on long stalks, sometimes with several sharing the same stalk. By comparison, the strobili of Lycopodium obscurum are stemless, not clustered (although a single plant may have several), and up to twice as long.

Spores. Clubmosses produce prodigious quantities of spores. They are extremely tiny. In late fall (and even this time of year if the cones are not frozen or water-logged) you can generate clouds of spores if you give the plant a little nudge. They stream off the stroboli like smoke from a flickering candle — not exactly a festival of light but the remains of one.

Unique. Clubmosses are the only plants in the entire plant world that have xylem and phloem arranged in the same way in both their stems and roots. In all other plants, the structure varies for stems and roots.

Reference. Boughton Cobb, A Field Guide to Ferns. (The Gleason Library has a copy of this book.)

2007 The Carlisle Mosquito