A Real Hidden Gem: Cranefly Orchid (Tipularia discolor)

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. 

Cranefly orchid flower stems with buds (encircled) almost invisible under the beech tree. Photo taken by Wendy Diaz on July 29, 2020

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]

Asymmetrical flower features of Cranefly Orchid resembling a crane fly. Photo taken by Wendy Diaz on August 9, 2018

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.

Green leaf with purple spots in winter. Photo taken by Wendy Diaz on November 3, 2018
Underside of the Cranefly Orchid leaf is purple in color. Photo taken by Wendy Diaz on November 3, 2018

The leaf originates from one small corm 0.7 to 3 cm (1/4 to about 1 inch) in diameter8

Features of the Cranefly Orchid: flowers, corm and leaf, bud and fruit[9]

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.

Flower stem emerging from leaf litter. Photo taken by Wendy Diaz on July 22, 2020
Cluster of flower buds on tip of flower stem. Photo taken by Wendy Diaz on July 22, 2020

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).

Flower stem grown in height and individual flower buds can be distinguished. Photo taken by Wendy Diaz on July 29, 2020

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.

Cranefly Orchid in full bloom. Photo taken by Wendy Diaz on August 7, 2019

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.

Close up of individual Cranefly Orchid flowers (less than 1 cm). Note long nectar spur on each flower. Photo taken by Wendy Diaz on August 7, 2019

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

An Introduction to the Durham Garden Forum

by Karen Lauterbach EMGV

Does the pandemic have you thinking about gardening?  Are you considering growing your own food, looking for a way to spend time outside in a rewarding hobby, or working to improve your home landscape? If so, you should know about the Durham Garden Forum (DGF), a valuable resource for Durham residents and others in the Triangle area.

Now entering its 11th year, the DGF holds lectures once a month on a variety of gardening subjects, including growing vegetables, garden design, composting, tree care, controlling invasive plants, and gardening with native plants.

Since its inception in 2009, DGF meetings have been held at Sarah P. Duke Gardens from 7 to 8:30 pm on the third Tuesday of each month.  In March 2020, DGF moved online via Zoom. Since then, meeting invitations have been sent each month to all DGF members and Durham County Extension Master Gardeners. 

“We created Durham Garden Forum to provide members of our gardening community with research-based learning on a monthly basis at low cost,” explains Gene Carlone, one of the DGF founding members along with Rick Fisher, who was also an extension master gardener volunteer.  “We recruit qualified and effective speakers to present research-based information on a variety of gardening topics. Through our lectures, we inform the gardening community of resources available to improve gardening techniques and practices.”

And for the past two years, DGF has also provided a venue for plant sharing, with members bringing excess plants and leaving them on the plant-giveaway table.

“This service has been temporarily suspended while we meet via Zoom, but will be up and running again when we next meet in person, probably with a lot of pent-up supply and demand,” Carlone added.

DGF will be an online lecture series for the coming year. If you have not been receiving invitations to DGF online programs and would like to receive a meeting invitation, send your request to durhamgardenforum@gmail.com.  You will be added to the email distribution list.

Here are the dates, times and topics for upcoming lectures:

  • August 25, 2020; 7:00 – 8:30 pm – Beyond Daffodils and Tulips (a review of all geophytes, including bulbs, corms, tubers, rhizomes, and tuberous roots)
  • September 15, 2020; 7:00 – 8:30 pm – TreesDurham (A review of historical policies that have created today’s inequitable tree distribution in Durham)
  • October 20, 2020; 7:00 – 8:30 pm- Hosta! (gardening with hosta, with a look at some of the newest varieties)
  • November 17, 2020; 7:00 – 8:30 pm – Houseplants 101 (how to bring the garden indoors)
  • December 15, 2020; 7:00 – 8:30 pm – Ten Mothers Farm (learn more about growing organic, nutrient-rich vegetables)
  • January 19, 2021; 7:00 – 8:30 pm – Extension Master Gardener Volunteer Tomato Grafting Project
  • February 16, 2021; 7:00 – 8:30 pm – Reptiles and Amphibians In Your Garden (learn about the variety of reptiles and amphibians in our area, separating truth from myth)

Topics for the remainder of 2021 will be announced as the program schedule is finalized. 

Questions?  Contact durhamgardenforum@gmail.com.

July: To Do in the Garden

by Gary Crispell

2020, the year of COVID-19, quarantine, ubiquitous face masks and toppling Civil War monuments. “The times they are a changin’.”  (Thank you, Bob.)

Speaking of changing; Wasn’t June fun in the garden? There was weather to suit almost everybody. (All you snow lovers ain’t ever going to be happy here, so get over it.) We had dry & cool, and dry & hot, and wet & hot, and wet & cool, and wet & wet (though never wet & dry). In between all of those were some really nice days which if you didn’t blink you could have enjoyed.

My “Accidental Cottage Garden” is looking like … well, an accidental cottage garden. The many-hued season has given way to the yellow and violet season. There are coreopsis (Coreopsis lanceolata & C. verticilata), black-eyed Susans (Rudbeckia fulgida), prairie cornflower (R. hirta) and a spreading chrysanthemum that blooms nearly all summer (and is yet to be identified by me) all screaming yellow.  The violet is provided by liatris (Liatris spicata), purple coneflower (Echinacea purpurea), Stoke’s aster (Stoksia leavis), balloon flower (Platycodon grandifloris) and some lingering cornflowers (Centaurea montana). A couple of counterpoints have just bloomed, butterfly weed (Asclepeis tuberosa) and a variety of Asiatic lily (Lilium x ‘Corsica’). The Limelight hydrangea (Hydrangea paniculata ‘Limelight’)  is fixin’ to bust out, but the Knockout rose has succumbed to the ravages of voles. There appears to be something new every day.

Oh! I almost forgot. Y’all came here looking for a calendar of stuff to do in July in the garden. Just for you, here ‘tis.

Lawn Care
Fertilize warm season grasses (Bermuda, Zoysia and St. Augustine) if you haven’t already.

When mowing these lawns remove one-third of the growth.

Change directions with each mowing to strengthen root systems and expose different side of the blades of grass to sunlight.

Fertilizing
Continue side-dressing your vegetable garden plants.

July is the last time to fertilize landscape plants until next year.

This is an excellent time to take soil samples especially from your lawn. Sample boxes and instructions can be obtained from the extension office. It is a FREE service until mid-November.

Planting
Veggies that can still be planted include Brussels sprouts, collards, beans, carrots, tomatoes* and pumpkins.

Get ready for the fall garden by starting broccoli, cabbage and cauliflower plants to be transplanted in mid-August.

This is also a good time to transplant overgrown houseplants.

Pruning
“Bleeder” trees like maple, dogwood, birch and elm can be pruned this month.

Overgrown hedges can be pruned.

Keep garden mums pinched until mid-month.

Coniferous evergreens (they make cones with seeds in them) can be pruned.

Raspberry and blackberry fruiting canes can be cut to the ground following harvest.

Remove faded blooms on perennials to encourage a second blooming. (Or let them go to seed and feed the birds.)

Rhododendrons, azaleas – I know that’s redundant – and blueberries can have the dieback removed.

Spraying
Insects to be watchful for include bag worms, leaf miners, aphids, spider mites and lace bugs. Oh, yeah.  Japanese beetles, duh.

Watch tomatoes* for signs of blight and spray as necessary.

Continue with rose program.

Also continue fungicide program for bunch grapes and fruit trees.

Vegetable pests to be on the lookout for:  cucumber beetle (cucumber, ironically enough), flea beetle (tomato, eggplant and beans) and aphids (everything).

Only use pesticides when necessary and ALWAYS follow the label instructions.


Not too many extra things to do this month unless you want to build cold frames and greenhouses to be ready for next winter. I recommend you kick back on the deck in the evening with a cool beverage and enjoy summer in this the “goodliest state.” 

*Speaking of tomatoes, visit our Tomato Grafting Project page for an update about this special project! Learn more

Beech Leaf Disease Mystery: A Nematode is the Main Suspect

By Wendy Diaz EMGV

One of the trees in the north corner of my triangle-shaped yard that has a very large presence and provides beneficial shade is a native American beech tree (Fagus grandiflora)1. I love my beech tree and it came with the house as the developer left a forested buffer along the back property boundary. Its low branches of bright green leaves and its smooth grey bark on its wide trunk contrast nicely with the rough-textured bark of the mainly tall bare narrow trunks of the pine, white oak and sweet gum trees that dominate our backyard. So, when I heard2 about a new disease called Beech Leaf Disease (BLD) affecting these beautiful trees in Northeastern Ohio, I became concerned and wanted to learn more. 

American Beech in my backyard. Photo by Wendy Diaz May 28, 2020

American Beech Primer

The American beech is an important anchor species or ‘foundational species’ which means other living organisms and the functioning of the forest ecosystem depend on these beech trees3. This important deciduous tree of our Eastern forest is slow growing and can reach about 80 feet in height and a lifespan of between 300 and 400 years1. The American beech is a common shade tree and is most recognizable by its distinctive smooth gray bark which it maintains throughout its lifespan unlike other hardwood species. The smooth light bark tempts many a knife carver and it often has letters carved in its bark along trails in the state. Its nuts are an important food source for wildlife and a favorite of blue jays. Beech trees have shallow root systems and prefer well-drained acidic soil4. The serrated oblong leaves turn golden yellow in the fall.

BLD Discovery and Spread

In 2012, Beech Leaf Disease was first discovered by John Pogacnik, a biologist, in a beech tree grove atop a ravine in Concord Township north of Columbus in central Ohio5. As of January 2019, the disease had spread as far north as southern Ontario in Canada and decimated large tracts of beech trees in many counties in Northeast Ohio, Western Pennsylvania and New York. In October 2019, the disease was confirmed in Connecticut and Long Island. It spreads about 150 miles eastward each year and movement towards the east has been rapid but movement to the west has been much slower. The map below illustrates the distribution of the BLD disease.

Image courtesy of Ohio Department of Natural Resources website http://forestry.ohiodnr.gov/pests

Suspected Source

To date the cause of the disease is unknown. Suspects include a new species of nematode discovered in 2017 by Dave McCann, a plant pathologist of Ohio Department of Agriculture. He observed 2mm long nematodes when he examined diseased leaves under the microscope5.  Lynn Carta, a plant disease specialist with the U.S. Department of Agriculture (USDA) in Beltsville, Maryland first described the new nematode as a subspecies of nematode described by Japanese scientists and named it Litylenchus crenatae ssb mccannii (Anguinata) 6. This is the first example of a leaf-eating nematode infecting and potentially killing a large live forest tree in North America according to L. Carta and it may have originated in a Pacific Rim country. Nevertheless, Enrico Bonello, a plant pathologist at Ohio State University, found nematodes in both healthy and diseased leaves so he attributes the true cause of the disease to a microbial pathogen and postulated that the microscopic worms may be simply transmitting the pathogen.7

Litylenchus crenatae mccannii (Anguinata) Possible suspect of the cause of Beech Leaf Disease is this newly discovered nematode from Asia. Photo courtesy of USDA/ARS/ELECTRON & CONFOCAL MICROSCOPY UNIT/LYNN CARTA/GARY BAUCHAN/CHRIS POOLEY/MYCOLOGY AND NEMATOLOGY GENETIC DIVERSITY AND BIOLOGY LABORATORY; COLORIZATION BY IT SPECIALIST/SOYBEAN GENOMICS AND IMPROVEMENT LABORATORY

BLD Symptoms

Diseased beech leaves exhibit interveinal greening or dark green bands between veins of the leaf, thickening and often chlorosis in leaves6 and sometimes leaves blister, thicken and become shriveled. Later, the diseased leaves become uniformly darker, shrink and get crinkly8,9. Eventually the canopy starts thinningand limbs stop forming new buds and eventually the tree dies. The disease has been found in European and Asian beech tree species in nurseries and at the Holden Arboretum in northeastern Ohio.

Classic dark green banding between veins of beech leaves and symptom of Beech Leaf Disease (BLD). Photo courtesy of Ohio State University Buckeye Yard & Garden online article entitled More Beech Diagnostics, author Jim Chatfield. Published on August 28, 2017
No dark banding between leaf veins in healthy Beech leaves. Photo taken by Wendy Diaz May 28, 2020

What can we do now? Not much because they don’t know how it spreads as yet10. We have to try and prevent the introduction of BLD to our southeast forests and monitor them for signs and symptoms of the disease11. USDA’s Animal and Plant Health Inspection Service, the agency responsible for dealing with invasive tree killers, is also studying the disease but is not taking action to limit the disease until more is known about how the disease spreads and its cause.7 In the meantime people can help with BLD surveys by downloading the Tree Health App3 and it is always a good practice not to move firewood between locations. If you purchase European and Asian varieties of beech trees be careful because long-range spread is probably assisted by anthropogenic transport, especially of nursery stock8. Let us hope they determine the cause and discover a remedy soon before this disease spreads south to our beech forests here in North Carolina. For now, I will pay more attention to my beech tree and spread more leaf litter over its shallow roots to prevent stress during our summer dry spells and I definitely won’t be carving my initials its smooth bark.

Closeup of smooth gray bark of the American Beech. Photo taken by Wendy Diaz May 28, 2020

References:

  1. http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=a865
  2. https://www.npr.org/2019/08/07/749163959/a-mysterious-disease-is-killing-majestic-beech-trees-in-american-forests
  3. https://www.news-herald.com/news/geauga-county/potentially-deadly-beech-tree-disease-affecting-northeast-ohio/article_b9bf9426-9366-11e9-9988-238e40b7b140.html
  4. NCSU Plant Toolbox: https://plants.ces.ncsu.edu
  5. https://www.cleveland.com/metro/2018/05/newly_discovered_microscopic_w.html
  6. Carta LK, Handoo ZA, Li S, et al. Beech leaf disease symptoms caused by newly recognized nematode subspecies Litylenchus crenatae mccannii (Anguinata) described from Fagus grandifolia in North America. For Path. 2020;00:e12580. https://doi.org/10.1111/efp.12580 Link (https://www.ars.usda.gov/ARSUserFiles/2279/20updated%20Litylenchus%20crenatae%20maccannii%20Forest%20Pathology%202020%20Published%202.17.20.pdf
  7. https://www.sciencemag.org/news/2019/11/mysterious-disease-striking-american-beech-trees
  8. https://www.dontmovefirewood.org/pest_pathogen/beech-leaf-disease/
  9. Ohio State University More beech diagnostics Jim Chatfield August 28 2017 https://bygl.osu.edu/node/885
  10. https://ohiodnr.gov/wps/portal/gov/odnr-core/divisions/division-forestry/related-resource/Beech-leaf-diseasePublished on May 17, 2020
  11. https://www.forestinvasives.ca/Meet-the-Species/Pathogens/Beech-Leaf-Disease#86229-impacts

Note: At the time of this post not all resources were accessible as the Ohio Department of Natural Resources and Division of Forestry website was under redevelopment.