Something Completely New (to Me)


While doing photographer’s yoga trying to get decent pictures of princess pine, I happened to spy something different. Carefully making my way down a wet slope, then squatting and bracing against a beech tree, I was able to photograph several clumps of this plant: Huperzia lucidula, commonly known as firmoss or shining clubmoss.

Like the Dendrolycopodium in my last post, firmoss is a vascular plant that reproduces via spores rather than seeds, and is in the Lycopodiaceae.  It ranges across the eastern US, in wooded ravines and hillsides and other shady, moist places with plenty of leaf litter.  It grows in clumps, with the vertical stems reaching no more than eight inches tall.


This plant is completely new to me, made more exciting because I found it in freaking January.

Tree Wolf Foot



overhead shot; beech leaves on the ground give a sense of scale


Last summer I wrote about a flowering plant in the genus Lycopus. This post is about something completely different, way far away in the taxonomic hierarchy, a vascular but not seed-bearing plant in the genus Dendrolycopodium (family Lycopodiaceae).



the “cone”, properly known as a strobilus, which contains the spores


Commonly known as ground pine, or princess pine, or clubmoss, it isn’t a pine, nor a moss. Vaguely related to ferns (in that they reproduce via spores rather than seeds), these primitive plants are covered in simple, single-veined, needle-like leaves. A plant consists of an underground stem with vertical shoots that seldom exceed twelve inches tall.



look how tiny those leaves are! no more than a quarter of an inch long


There are four species within this genus, three of which can be found in eastern North America. According to BONAP and the Maryland Biodiversity Project, only one of those species is found in Montgomery County, and for that reason (rather than properly keying out a specimen), I’m calling this one Dendrolycopodium obscurum, which in addition to the above names is also called flat-branched tree clubmoss.



who loves acidic soils? princess pine (Dendrolycopodium obscurum) growing with prince’s pine (Chimaphila maculata) – no kidding!


This species seems to be found mostly in the upper Midwest, New England, and the Appalachians. It’s rare in Indiana and exploitably vulnerable in New York. It likes moist, acidic soils in woodlands. As I wrote a few days ago, I found an extensive stand on a slope near several species in the Ericaceae, which as a rule of thumb like acidic soils.

This isn’t a rare plant, but it’s unusual to find a big stand of them. This is a good time of year to look for low-growing evergreen forbs. And if you’re a geek like me, you’ll geotag a picture so you can find them again.

Peripheral, But Not Insignificant


marginal wood fern, marginal shield fern, leather fern
Dryopteris marginalis

beautiful specimen near Snyder’s Landing, June 2015


While out looking for something green (other than Christmas fern and rock polypody), I found marginal wood fern.  “Marginal” not because it’s insignificant, but because the sori are located along the margins of the pinnules.



sori along the edges of the pinnules


Marginal wood fern is widespread across the eastern US and Canada, except in Iowa and Minnesota, where it’s threatened.  New York lists it as exploitably vulnerable.



scaly stipes


Like so many ferns, it likes a damp habitat.  In the Maryland Piedmont look for it in ravines and rocky slopes.  I found dozens of them clambering over cliffs at the edge of Cabin John Creek, in an area that’s always wet from seeping groundwater.



groovy – er, grooved – rachis

In Search of Something Green (and Native)

American holly (Ilex opaca) on the Cabin John Trail


After two weeks battling a sinus infection, I finally felt well enough to go for a hike. Well, more of a walk. As I’ve written before, the Cabin John Trail is treacherous: an over-used trail with poor footing in many places. But, I almost always find something worthwhile, if I take the time to poke around and really look at things.

And so it was yesterday. I knew I’d find a lot of Christmas fern, but went with the goal of finding something else – and I did, after scrambling about in a dryish seasonal watercourse. Look for a post about that fern in another few days.

After that I went to a section I call Erica Alley. It’s a very rocky slope with a high concentration of mountain laurel (Kalmia latifolia), and big stands of rock polypody. There I found several small stands of spotted wintergreen (Chimaphila maculata, another ericaceous plant), which thrills me because I failed to find it near Carderock this year. And then, poking about, I found something completely new. And something old that required re-inspection.

I don’t carry ID books with me. Whenever I have a book, I end up plopping my butt down and reading for 20 minutes. I’m too easily distracted by “dictionary syndrome”. So I take pictures, but often fail to get the right pictures for a definitive ID. At least I’ve narrowed them down to the correct genus. Perhaps if the weather’s good today I’ll go out again, this time with the ID books, dammit.

If you see a middle-aged woman reading a book on the Cabin John Trail, say hi.

Many Little Feet


Common or rock polypody, American wall fern, rockcap fern
Polypodium virginianum

a small stand on the Cabin John trail


This little fern is no less charming for being incredibly common.  It’s found throughout most of the eastern US and Canada except for parts of the deep south.  Although short (the fronds are usually about twelve inches long), the rhizomes will form massive colonies in suitable habitat, which consists of all sorts of rock outcroppings and rocky soils in moist shade.



an itty-bitty specimen at Carderock; it doesn’t have much soil to grow in!


It’s also an easy fern to identify, especially at this time of year, since it’s evergreen.


new fronds in late April along the Cabin John trail

Conservation Terminology



Erythronium albidum, listed S2 in Maryland



After a recent post, a friend asked what “exploitably vulnerable” meant. Which got me thinking, I usually report the conservation status of the plants I write about, but have never defined these terms.  So here’s a little primer.

Some time ago, The Nature Conservancy devised a system for ranking the rarity of plant species on a global scale*.  Many organizations and government agencies started using this system, or devised their own system based on it. The global system looks like this:

G1 – critically imperiled throughout its range due to rarity (5 or fewer sites or very few remaining individuals) or other factors
G2 – imperiled, high risk of extinction due to restricted range, low number of populations, or other factors
G3 – moderate risk of extinction due to range, number of populations, etc.
G4 – apparently secure, uncommon but not rare, some cause for concern
G5 – demonstrably secure throughout the range
GX – believed extinct, rediscovery unlikely
GH – known historically, currently no known occurrences, some hope of rediscovery



Scutellaria nervosa, listed S1 in Maryland




When I write about a plant’s conservation status, I use data from the USDA Plants Database. I presume (but am not sure) that their reporting of rank comes from the various state agencies; certainly they are using each state’s terminology. And that’s where things get interesting.

Each state has essentially the same system of classification, based on the global ranking system, but with some variation in terminology and definitions. Thus, the state of Maryland’s ranking system goes

S1: Highly State rare. Critically imperiled in Maryland because of extreme rarity (typically 5 or fewer estimated occurrences or very few remaining individuals or acres in the State) or because of some factor(s) making it especially vulnerable to extirpation. Species with this rank are actively tracked by the Natural Heritage Program.

S2: State rare. Imperiled in Maryland because of rarity (typically 6 to 20 estimated occurrences or few remaining individuals or acres in the State) or because of some factor(s) making it vulnerable to becoming extirpated. Species with this rank are actively tracked by the Natural Heritage Program.

…and so on.


Valeriana pauciflora (S1)




Based on these rankings, Maryland has a status list: Endangered, In Need of Conservation, Threatened, and Endangered/Extirpated (and a few more).

For Rhode Island, the status list is: State Endangered, State Threatened, Concern, State Historical.

For New York the status list is: Endangered, Threatened, Rare, Exploitably Vulnerable, Unprotected.

These are the phrases I’m reporting in my posts. The exact definition of “endangered” may vary from state to state, but it’s safe to assume that endangered is always the most imperiled condition, threatened is next, then rare, then come the terms like “exploitably vulnerable” or “special concern.”

You may be wondering, have I ever found any rare plants? Sure. I wrote about climbing dogbane last June, and I’ve found a few other S1s and S2s, and quite a few S3s, and reported them to the DNR when appropriate. Since I haven’t memorized the sadly long list of rare, threatened, and endangered plants in Maryland, it’s only after I return home and start researching that I realize what I’ve found. Such a discovery is often followed by a clearing of my calendar so I can get back to the site as soon as possible and get more and better pictures, and geotag them.

It’s rather like a treasure hunt, except of course I only observe them, and make damn sure I’m not harming them or their environment.


Dirca palustris (S2)


* for much of the information in this post I am indebted to the publication “Rare Native Plants of Rhode Island” by Richard W. Enser of the Rhode Island Natural Heritage Program, and NatureServe.  I was unable to find the original source material on the global ranking system, but found several other state websites that described the global ranking system; all used minor variations on the same language.