Wintergreen Orchids

Due to excessive reliance on TV and movies for general information, I once consider orchids to be rare exotic blooms: kidnapped from a tropical jungle; added to a collection in a misty Victorian hothouse tended by a rich, eccentric geezer; each specimen nestled in a bed of purloined opals and spoon-fed a diet of dried puppy blood. So, finding orchids in a local woodlot in winter was eye-opening. In fact, we found healthy populations of two species.

Orchid habitat ... no jungle, no Victorian hothouse, no puppy blood

Both species pass the winter with a single leaf poking above the forest litter from a root-like stem (corm). Each leaf appears in autumn and withers in spring, a specialization for life on the floor of deciduous forests. During the warm season, the forest floor is shaded by the leafy tree canopy, and there is intense competition among plants for access to the few remaining sunny spots. But there is abundant sunlight during the winter, after the trees have all gone naked and the competitors have gone to seed or are otherwise MIA. The wintergreen orchids can photosynthesize during the colder months and, like most orchids, they probably also get a nutritional boost from helpful soil fungi.

There appears to be a cost to this otherwise clever strategy: the orchids may not generate enough reserves during a single winter to either push up new flowers in the following summer or split off a new plant by subdividing underground. So reproduction may be deferred in exchange for a reliable refuge from the hustle and bustle of warm-season competition in the plant world.

The first orchid we came across was the Puttyroot (Aplectrum hyemale), with its tapering green leaf decorated with white pinstripes, usually only a step or two from a beech tree (Fagus grandifolia). The orchid is the sole member of its genus and occurs only in the forests of eastern North America. We've found a fair number of singletons. But there are also scattered clusters of two to several leaves, probably families of clones descended from a single founding plant. If flowers show up at all, they appear in May to June on a stalk of about a dozen green and purple-tinged blooms. The flowers offer no nectar, although the stumbling and bumbling of native bees may dislodge some pollen onto the stigma of the same flower. Experiments have shown that this will happen even without buggy interventions. Cross pollination is either exceedingly rare or non-existent. One of the army of tiny seeds that result from self-fertilization may produce a new plant if it happens to land on a spot where a friendly fungus will nurture it. This seems to be a rare event. 

Two Puttyroot Orchids (Aplectrum hyemale) (Southwestern Baltimore County)

Various corners of the internet claim that the Puttyroot is named for a gluey mucilage produced by crushing the corm. The "putty" can apparently be used to repair broken pottery. This is almost interesting in itself and gives some insight into what people were up to before television. It also makes me wonder about the product development behind Gorilla Glue and Frog Tape.

The other wintergreen orchid in the woodlot is the Cranefly Orchid (Tipularia discolor). It's the only member of its genus in North America, although it has kin in East Asia. The leaf isn't as narrow as the Puttyroot and lacks the pin stripes, but it may have a smattering of raised purple spots. The central vein rests in a valley, while the neighboring veins ride along ridges, giving the leaf a pleated appearance. The underside is a deep purple.

Left: Two Cranefly Orchids (Tipularia discolor), upper surface showing pleating and purple spots. Right: Deep purple under surface.

Its flowers are similar to those of the Puttyroot, but appear in mid to late summer. Each stalk may get about 20 inches high and carry a dozen or so flowers. However, unlike Puttyroots, the flowers are built to attract pollinating insects, especially moths. Each flower has a nectar spur, a long tube that entices the moth to enter the bloom to ensure that pollen attaches to the small hairs (setae) associated with the insect's eye. The stigma apparently remains hidden until the pollen is gone, thus reducing the chance of self pollination.

We are looking forward to finding the flowers of both orchid species later this year. However, we have been disappointed to find that the woodlot has been invaded by dirt bikers, who apparently have the right to trash the place as they see fit. Within the last few weeks, they have blazed trails throughout the forest and have already run over some of the orchids.Tragedy of the commons.

Dirt biker JT marks his territory on a beech tree. A fine lad, I'm sure.

Follow the these links for more info on Puttyroot Orchids and Cranefly Orchids.