Green in Winter: Running Ground Pine

Lycopodium clavatum has an affinity for thinly wooded sandy acid flats in northern LaPorte County in Indiana. It is occasional in Porter and Starke Counties, and has been discovered in a few northeastern counties as well. It sometimes occurs in red maple swamp forests that are not too wet.

Interestingly, Charles Deam excluded it from his Flora of Indiana (1940) because he had not seen it, and while a few others had reported it, no specimen had been preserved. Though rare, this plant was already somewhat frequent when I began botanizing in the 1980's, so it expanded its range in a mere 40 years. Photographed in LaPorte County, Indiana on December 31, 2011.

Green in Winter: Ground Cedar and Running Ground Pine

Exceedingly rare in Indiana, the little-known and poorly recognized Ground Cedar (Lycopodium tristachyum) is occasional in semi-dry, sandy, early-successional flats behind the dunes, mainly in LaPorte County. This plant is sometimes called Diphasiastrum tristachyum.

Photographed in LaPorte County, Indiana on December 28, 2011.

It is similar to the somewhat common Running Ground Pine or Fan Clubmoss (Lycopodium complanatum var. flabelliforme) shown below, but the latter has horizontal stems at the surface and “leaves” on the lower side of the branch much reduced and not overlapping. In addition, the antrorse lateral leaves of the latter are slightly more appressed, a little less spreading.

Photographed in LaPorte County, Indiana on December 31, 2011.

One could make a full time job out of trying to stay current with the bothersome revolving door of clubmoss nomenclature. To wit, the latter species has the following handles involved in its identity crisis: Diphasiastrum digitatum, Lycopodium digitatum, L. complanatum, L. flabelliforme, and L. complanatum flabelliforme. Some botanists feel obligated to provide all 4011 names so as not to offend anyone’s tender sensibilities, alas.

Interesting Little Forest

Does this young forest look mundane? Uninteresting?

It’s quite the opposite!

At a fraction of an acre, it occupies a little corner in a long-abandoned ag field in St. Joe County, Indiana – out of cultivation for at least 30 years. Most of the surrounding land is yellow clay at the surface, and forests in the vicinity are Beech-Sugar Maple. But this little corner is dominated by Red Maple, with occasional Black Cherry and Sassafras on a sandy substrate. Unlike other Red Maple forests, this one is not in a low lying flat, but upland. The sand is almost certainly underlain with clay, keeping moisture at the surface for long periods of time.

When Red Maple forests aren’t too shady the herbaceous vegetation can be pretty exciting, especially if you like ferns, club mosses, and sedges. I first botanized this site in 1997 and found hundreds of Daisyleaf Grape Ferns (Botrychium matricariaefolium).

In 2008 I was startled to find Downy Rattlesnake Plantain (Goodyera pubescens) and Spotted Wintergreen (Chimaphila maculata).

Downy Rattlesnake Plantain Orchid (Goodyera pubescens)

Spotted Wintergreen (Chimaphila maculata)

Last week I went there to photograph Botrychium dissectum and its segregates and was fortunate to see a tiny Spiranthes orchid in seed. Its identification is guesswork, but diminutive Spiranthes ovalis is a possibility.


On the same visit I saw the lovely Shining Club Moss (Lycopodium lucidulum)!
Interestingly, the club moss was growing right at the base of a tree where water gets funneled when it rains. If you’ve never observed this, it’s worth donning a rain suit and going into the forest while it’s raining. All of the water that doesn’t drip from a tree’s limbs or get absorbed by the bark gets funneled right down the trunk, and even during moderate rain, water comes gushing down. Some plants take advantage of this. For example, Spinulose Wood Fern (Dryopteris spinulosa) will grow anywhere in mesic and wet forests, but in dryer sites it survives at the base of tree trunks. Watch for this – it’s a common sight, at least in northern Indiana. Dryopteris intermedia does this too, as shown in this photo from Warren Woods in Michigan. We should keep this in mind when doing native landscaping. And we should never pass up a chance to botanize a Red Maple forest!

Florist's Fern (Dryopteris intermedia)

Shining Club Moss (Lycopodium lucidulum)

Dark green and super shiny all year, this plant is one of many that are easier to find in winter. Unlike other club mosses in Indiana, it does not produce a strobilus (cone-like structure bearing sporangia). Instead, sporangia are borne in leaf axils along the stem. Another interesting variation is its production of gemmae - little vegetative propagules that fall off, take root, and produce new plants. Shining Club Moss grows in high quality swamp forests on mossy hummocks, and occasionally on slopes in mesophytic woods. Photos from a steep, riparian slope at Warren Woods in Berrien County, Michigan.

Lycopodiums

Lycopodium obscurum (Ground Pine, Princess Pine)

Lycopodium complanatum v. flabelliforme (Trailing Ground Pine)

Lycopodium clavatum (Running Ground Pine)


Lycopodium tristachyum (Ground Cedar)

Lycopodium lucidulum (Shining Club Moss)

It was a spectacular day in Sebert Woods! Blustery winds brought down all manner of brightly colored leaves (as well as large limbs) and it was marvelously mosquito-free! I was reminded of Margeret Micklethwait’s line: “Sometimes a rough wind surges through the trees, making a sound like wild and stormy seas, and rushing waves…” Photos from the day include Lycopodium obscurum, L. complanatum flabelliforme, L. clavatum, L. tristachyum, and L. lucidulum. Some of these club mosses are now being called by outlandishly different names, and I’ll hop on that bandwagon eventually. In the meantime, if anyone is splitting the Lycopodium obscurum/dendroideum/hickeyi complex, please feel free to comment. What a pleasant autumn day!