Crane-fly orchid (Tipularia discolor) of the Orchidaceae (Orchid) Family is the only species of the genus found in North America. This perennial plant is found in the eastern US (except New England), west to Illinois and south to Texas. In Arkansas, the species occurs throughout much of the southern half of the state in the Gulf Coastal Plain and Ouachita Mountains, also extending up the Arkansas Valley and into portions of the Boston Mountains. It additionally can be found on Crowley’s Ridge. Habitat is moist, fairly rich soils on slopes and terraces of oak-pine forest and woodlands, often in sandy soils, but it sometimes also occurs in wetlands. Underground portions of crane-fly orchid consist of a series of connected edible corms with a few fibrous roots radiating form their bases. One to a couple of new corms branch off the previous corm so that, over time, sizable clumps can develop. Newly forming corms produce a single winter-time (hibernal) leaf that grows directly from the corm.
Glabrous leaves, appearing in late fall, mature to have a semi-glossy, dark green upper surface and strongly purple lower surface. Leaves, with acute tips, are up to 3 inches long and elliptic with parallel veins. Slight up-folding along veins gives leaves a convex corrugated appearance. The upper surface is often marked by raised purple spots. Winter-time leaves, easily seen in contrast to the decaying leaves and branches of a woodland floor (duff), lie mostly flat on the ground. Leaves persist through winter months and then wither well before flowering in summer.
Photo 1: Two new corms of crane-fly orchid growing from “current” corm. “Current” corm produced an inflorescence in previous summer. (Photo date: November 20, 2014)
Photo 2: Crane-fly orchid leaves showing strongly purple color of lower leaf surface and raised spots on upper surface. (Photo date: April 14, 2014)
At flowering in late summer, straight peduncles (flowering stems) with multiple flowers emerge from the duff. Flowering stems of crane-fly orchid occur singly from corms that developed and had leaves the past winter. Flowers, on pedicels (stems bearing individual flowers), occur along the upper half of peduncles in raceme-like inflorescences with all flowers (20 or more) maturing at the same time. Although peduncles are tall (15-18 inches), their obscure color and that of the flowers cause inflorescences to be difficult to see in summer-time woodlands.
Down facing flowers, ½ inch across, are greenish to purplish. Flowers have three sepals and two lateral petals. Flowers are asymmetrical (unusual for an orchid) due to the dorsal sepal and lip (labellum) being off-set to one side on the central axis. Also, one lateral petal is typically twisted down so that it overlaps the adjacent lateral sepal. Flowers have a spindly crane-fly-like character, hence the name. The lobed lip of the column, a modified third petal of irregular shape, attracts insects and provides a landing platform. A long spur (nectary), more than twice the length of the remainder of flower, extends back from the lip. Pollen packs (pollinia), attached to the eyes of noctuid moths, are transferred from flower to flower.
Photo 3: Crane-fly orchid peduncles with flowers. All flowers open and mature simultaneously. (Photo date: August 10, 2014)
Photo 4: Spindly and asymmetrical flowers said to resemble crane-flies. Note long nectary and adjacent “inferior” ovary. (Photo date: August 23, 2014)
After pollination, flowers form round, elongated, dangling seed capsules with slightly corrugated surfaces. Peduncles with capsules become dry and tan-colored and persist even when new leaves emerge in fall. Capsules contain multitudes of yellowish-tan, dust-like seed.
Photo 5: Peduncles of crane-fly orchid with mature seed capsules. (Peduncles arranged for photo.) (Photo date: October 26, 2014)
Crane-fly orchids should be welcome in any garden with suitable habitat. The plants provide a focal point in winter-time gardens while being innocuous. Plants remain dormant through drought periods.
Article and photos by ANPS member Sid Vogelpohl