Plant of the Month January 2023: Cranefly Orchid

Cranefly Orchid, Tipularia discolor

January 2023 Plant of the Month

Northern Neck Chapter of the Virginia Native Plant Society

By Betsy Washington

As we celebrated the New Year with our annual New Year’s Day walk at Hickory Hollow NAP, many participants were intrigued by a small, common terrestrial orchid, the Cranefly Orchid, Tipularia discolor, that greeted us along the paths. Some were even more surprised to realize they had this orchid growing on their own properties! Oddly, this orchid is unique in having dark green leaves that appear in mid fall and remain handsome and dark green through the winter months despite the vagaries of winter weather and then wither away in late spring and early summer when the canopy closes overhead. This allows this forest floor dweller to soak up all the sunlight and accumulate energy stores during the winter while the canopies are bare, and sunlight can readily reach the forest floor. The single to sometimes large patches of oval dark leaves stand out against the brown and tan leaf litter in winter woods adding welcome color and life to a woodland landscape. Each leaf is smooth, about 3” long and wide with a pointed tip and if you look closely, you will notice the parallel veins running from the base to the tip as is characteristic of orchids and other monocots like lilies and irises. The leaves are smooth and dark green above with a slightly pleated appearance usually with purplish dimpled spots or bumps. Flip a leaf over and you may be surprised to find it is a rich dark purple – giving rise to the Latin specific name “discolor”, referring to the two distinct colors of the leaves. Research suggests this purple coloration on the bottom of the leaf may redirect energy-giving light waves back into the leaf tissue giving the chlorophyll another chance to use the otherwise escaping light. This intriguing orchid is found throughout the Eastern United States but is most abundant in the central part of its range. In Virginia it is most common in moist but well drained somewhat acidic forests in the coastal Plain and Piedmont and is limited to low elevations in the mountain province.

Each fall a single leaf emerges from an underground corm (storage organ) and if the corm has stored enough energy over the winter, a delicate leafless flower stalk rises from the bare ground in July and August. Loose, airy cluster of 30 – 40 pale greenish yellow to purplish brown flowers appear on the upper half of the stems, with each flower held on a slender drooping stalk so that they face downwards. The delicate flowering stem reaches only about 15 – 18” high and the small flowers are less than one inch wide. The flowers themselves are slightly asymmetrical, unusual for an orchid, with the narrow sepals and petals slightly angled towards one side – all to accommodate their pollinators. The slender sepals and petals and 3-lobed lip are nearly translucent - green to light purple. A long slender spur extends down behind each flower adding to the illusion of the long spindly legs of a cranefly giving this orchid its distinctive common name – Cranefly Orchid. These small flowers are cryptically colored and very hard to spot against the dappled shade of the forest floor in summer and often go completely unnoticed. The best way to find Cranefly Orchids to observe their delicate beauty in bloom is to get out in winter and look for the distinctive oval leaves with purple undersides and mark the spot so you can return in Mid-July to August to admire them. After the flowers are pollinated, numerous tiny dust-like seeds are contained in slender ribbed capsules that droop close to the stem and often remain standing well into the next fall and winter.

Although only a single leaf emerges from a corm, one to several new corms can branch off the current year’s corm creating a series of connected underground corms, surrounded by a mass of roots. Each corm throws up a single leaf in winter and a flowering stalk the following summer, however together they can create a large colony over time.

Like other orchids, Cranefly Orchid pollen is contained in tiny sacs called pollinia. All orchids have evolved specific and fascinating relationships for their flowers to be pollinated. Recent research has shown that small nocturnal moths, known as Owlet moths (family Noctuidae), pollinate the flowers by moving the tiny pollinia (which becomes attached to their eyes) from flower to flower as they seek nectar. There is some research evidence that specific owlet moth species have coevolved with orchid species as has been found in so many plants.

I am sure we would all love to have this unique orchid in our gardens but like many orchids, Cranefly Orchid is not a plant that can be easily grown. It cannot germinate and grow without specific mycorrhizal (fungal) partners, in this case, fungi that decompose rotting wood. So, if you have acidic woods on your property, be sure to leave some logs, branches or other woody debris along your paths and woods. You may well encourage a Cranefly Orchid to take up take up residence in your garden while the decaying wood also provides food, shelter and habitat for a diverse array of insects and pollinators which in turn provide food for birds and other wildlife. This little orchid speaks to the amazing mysteries and connections that are everywhere in our forests and natural areas so get out and investigate the woods on your property or take a walk at Hickory Hollow or another natural area and marvel at the plants and their connections even in the depths of winter.

Photo Captions:

Photo 1. The distinctive winter leaves of Cranefly Orchids (photo by Betsy Washington)

Photo 2. Detail of the delicate flowers of Cranefly Orchids (Photo by Kevin Howe)

Photo 3. Rich purple coloring of leaf undersides (Photo by Betsy Washington)

Photo 4. Cryptic flower color is hard to see in early August (Photo by Betsy Washington)