Since the topic keeps coming up on various internet forums, I thought I’d write a little guide about these plants, all of which are flowering or about to flower now in the Maryland piedmont.
sessile bellwort, Uvularia sessilifolia; Liliaceae or Colchicaceae
perfoliate bellwort, Uvularia perfoliata; Liliaceae or Colchicaceae
Solomon’s seal, Polygonatum biflorum; Ruscaceae or Asparagaceae or Liliaceae
Solomon’s plume aka false Solomon’s seal, Maianthemum racemosum; Ruscaceae or Asparagaceae or Liliaceae
(apologies for the family name confusion, but authorities differ)
In flower, these four species are easy to distinguish. Before they flower, they can be tricky – indeed, the old common name of M. racemosum comes from the fact that it looks a lot like P. biflorum.
So, how to tell them apart when they’re young?
I prepared this chart based on my own observations cross-referenced by information in the Flora of North America via efloras.org, the New England Wild Flower Society’s gobotany site, and Illinois Wildflowers.
||stems simple or with 1 branch
||stems erect or arching, sometimes zigzag
||stems erect to arching
||sessile or perfoliate (per species)
||sessile, clasping or perfoliate
||sessile to clasping
||oblong-linear to oblong-ovate
||elliptic to ovate
||narrowly lanceolate to elliptic or nearly ovate
||rounded to cuneate
||rounded to cuneate
||cuneate to rounded
||acute to acuminate
||acute or caudate
||glabrous, sometimes with a bit of a sheen
||1 per branch, terminal but appearing axillary
||axillary (in several axils)
||typically 2, as many as 5
The descriptions are much alike, and frankly not that useful when the specimens are still young. I don’t have all the pictures I want to illustrate this post, but study the ones below; I think with experience you can develop an eye for identifying these species by considering the whole plant as well as the individual details.
The bellworts are overall much smaller than the other two species, with shorter stems and smaller leaves.
Start with the easy one: perfoliate bellwort. The way the stem appears to pierce the leaf is unique, so it’s hard to confuse this with the others even when a specimen is very young.
Sessile bellwort is much smaller than M. racemosum and P. biflorum. Its terminal bud develops very early, when the plant is still tiny. Especially if the other two species are nearby, it’s pretty clear from the size and general appearance if a young plant is a bellwort.
perfoliate bellwort and Solomon’s plume next to each other; note how different the stems look (click to enlarge)
Perhaps the best way to distinguish M. racemosum from P. biflorum when the plants are very young is to look at the leaf tips. When the plants are a little older, they’re very easy to tell apart by looking for buds: M. racemosum has a cluster of buds at the very end of the stem, while P. biflorum will have a few buds at many (but not all) of the leaf axils.
I love that I found these two growing right by each other, but be warned, this P. biflorum is atypical: the leaves are exceptionally narrow. Note that there’s one flower bud dangling from a leaf axil. Also, check out the leaf tips (click on the picture to zoom in), because they’re textbook examples. P. biflorum’s is acute, and M. racemosum‘s is caudate.
P. biflorum with flower buds
young M. racemosum, no buds yet
zigzag stem, caudate leaf tips, and terminal inflorescence = M. racemosum
straighter stem, narrower leaves, and axillary flowers = P. biflorum