Green adder's-mouth is a native orchid

Spring is here, and it won’t get cold anymore. (Famous last words.) With spring comes a torrent of interest in gardening, and lots of money and effort are spent to this end on both small and large scales.

I am already getting a pile of requests for plant identifications, most of which end up being labeled as “weeds” by the person who sent them in. So, we ought to talk a bit about weeds.

There are various “folk” definitions of what a weed is. We commonly hear that a weed is a plant growing in the wrong place, which to me is actually a reasonable and practical definition. Of course, if you decide that you must move your rose bush to a new place in the yard, that doesn’t make it a weed.

Truly weedy species are generally able to reproduce quickly and abundantly, whether by seed or by various non-floral (vegetative) structures: rhizomes, runners, aerial or underground tubers, that sort of thing. Both annuals and perennial plants can be weedy species. As far as where weeds grow…it mostly doesn’t seem to matter. Most weeds could care less, and they don’t need a particular or special habitat in which to be happy.

Then comes the concept of introduced vs. native species as weeds. Sure enough, there are plenty of native species that don’t really care where they grow, and can actually be abundantly weedy: the common lyre-leaved sage (Salvia lyrata) is a good example.

To wrap up this discussion, consider also the term “invasive,” which is thrown around a lot. Scientific concepts of plant invasiveness, that is, plants arriving at a new place, well-removed from their native range, suggest that invasiveness is a process.

The casual introduction of a foreign plant species may not amount to anything…or this species may end up becoming “naturalized” and thus behaving as a native species, a good example being the worst weed in the USA, Japanese honeysuckle. Its stage of being invasive has succeeded completely, and now it has become part of the landscape!

Green adder’s-mouth, Malaxis unifolia, our Mystery Plant, is a native species, and it is not a weed. It is in fact an orchid, a tough little thing, reasonably widespread in all the eastern states, except southern Florida.

Like a weed, it doesn’t seem to care much where it grows, but is usually found in damp forests. It’s a terrestrial species, found on the ground, rather than growing as an epiphyte.

The plant will have a somewhat bulbous base, and a single egg-shaped leaf (sometimes two). The flowers are small and whitish, and someone thought an individual flower looks a bit like a snake’s open mouth. You’ll need a hand lens. The whole plant can be just a few inches tall, or up to a foot or so. Last year’s fruiting stalk may be attached if you find this in bloom now.

As with all wildflowers, please don’t pick or try to transplant to your yard, but just learn to enjoy in place. Besides, most attempts to transplant native orchids just don’t work.

John Nelson is the curator of the A. C. Moore Herbarium at the University of South Carolina, in the Department of Biological Sciences, Columbia, SC 29208. As a public service, the Herbarium offers free plant identifications. For more information, visit www.herbarium.org or call 803-777-8196, or email nelson@sc.edu.