By Wendy Diaz EMGV
Perhaps of all the North Carolina wildflowers I have tried to photograph, the hardest by far is the diminutive and well-camouflaged Cranefly Orchid (Tipularia discolor), which appears each August under my Beech (Fagus sylvatica) tree. I first became aware of its existence, only after representatives of the New Hope Audubon Society pointed to it as we toured my backyard during a Bird-Friendly Wildlife Habitat inspection. I wrote about this very educational visit previously for the Durham Master Gardener Blog in November, 2018[1].
The orchid flowers are tiny and delicate and blend in with the color of the leaf litter. The orchid plant is most easily identified in winter when its one leaf is present. In 2018, we only observed one orchid flower stem (inflorescence) but this winter several distinctive leaves appeared beneath the beech tree in four areas around the drip line of the beech tree. I marked these spots because the leaves disappear in early spring and for more than 2 months there is no visible evidence of the orchid’s existence until the flower stem pokes through the leaf cover in July. This year, the four areas have between 2 to 7 stems per colony for a total of 15 flower stems.
The Cranefly (crane-fly) or Crippled Cranefly Orchid is a member of the family Orchidaceae and the only species of the genus Tipularia (temperate terrestrial orchids) found in North America[2]. Its common name refers to its flower features, which look like the stilt-like legs, slender body and wings of a Crane Fly and the asymmetrical, or twisted arrangement of these flowers resembles the splayed legs of a crippled Crane Fly perhaps.[3]
Distribution
The Cranefly Orchid is native to the southeastern United States and occurs as far north as Michigan, as far south as Florida and west to Texas[4]. It can be found from the mountains to the coast in North Carolina and we are lucky to have secure[5] populations of this orchid because it is threatened in Florida and Michigan, listed as endangered in Massachusetts and New York, and rare in Pennsylvania[6].
Growing Conditions
Cranefly Orchids grow in woodlands with decaying wood and moist soils with high organic matter and good drainage. They need partial shade and some sun in the winter[7]. The large beech tree in my natural area is ideal as it is deciduous and looses its leaf cover in December. The orchid is also found in moist humus-rich soils of deciduous forests along slopes and stream terraces, in sandy acidic soils of oak-pine forests, and often in depressions under sweet gum (Liquidambar styraciflua) trees[8].
Leaf
Each orchid produces one oval-shaped basal leaf close, which only appears in the winter. The leaf emerges in November and is green with spots above and the leaf is a distinctive purple color below.
The leaf originates from one small corm 0.7 to 3 cm (1/4 to about 1 inch) in diameter8.
Flower
In early July, this very discrete native wildflower first emerges in the Piedmont as a small 7 cm (3 inch) tall spike and as it grows taller, a tight cluster of buds can be observed at the tip.
The orchid flowers eventually unfurl in August. The cluster of flowers (about 20) on each purple (more like burgundy to me) stem or inflorescence is about 8 to 28 cm long (about 4 inches to 1 foot).
Each irregular or asymmetrical flower is less than 1 cm in diameter with varying bloom color of yellow to greenish yellow or with a purplish[10] or copper-like color. There is a nectar spur on each flower that can be 1 to 2 cm long8.
The flower is pollinated by noctuid moths4, which are usually nocturnal and camouflaged to resemble tree bark. As the moth inserts its proboscis into the nectar tube pollinaria (specialized structures containing pollen) attach to the moth’s compound eyes and when the moth travels to the next flower it transfers the pollinaria to complete pollination. The flowers turn to oval-shaped fruits in the fall.
I can’t wait to see all the tiny orchid flowers bloom beneath my beech tree in the coming weeks this summer. Some things are best experienced in person because a camera cannot always capture the sparkle of this tiny gem of a wildflower.
References:
[1]https://durhammastergardeners.com/2018/11/07/create-a-bird-friendly-habitat-and-receive-recognition/
[2] Classification page: https://plants.usda.gov/core/profile?symbol=TIDI
[3] https://virginiawildflowers.org/2015/08/27/cranefly-orchid-or-crippled-cranefly/
[4] https://www.fs.fed.us/wildflowers/plant-of-the-week/tipularia_discolor.shtml
[5] https://goorchids.northamericanorchidcenter.org/species/tipularia/discolor/
[6]Legal status page- https://plants.usda.gov/core/profile?symbol=TIDI
[7] https://plants.ces.ncsu.edu/plants/tipularia-discolor/
[8] http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220013573
[9] Drawing Britton, N.L., and A. Brown. 1913. An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols. Charles Scribner’s Sons, New York. Vol. 1: 573.
[10] https://www.wildflower.org/plants/result.php?id_plant=TIDI