A Rare Orchid on the Prairies

Late June.  When the heightened humidity begins to make your clothes stick and the hum of annual cicadas rings in your ears; when the sun seems to hang motionless in the western sky and the raspberries are just about ripe, I know it's time to make my annual pilgrimage to a very special slice of Ohio.

E. Prairie Fringed Orchid (Platanthera leucophaea)

In a wet sedge meadow that seems no different than the rest but for a few short weeks each summer lives one of North America's most rare and spectacular of orchids: the eastern prairie fringed orchid (Platanthera leucophaea). I've posted on this site and species in years past but it deserves a breath of fresh air and some more attention as one of your blogger's most treasured of plants.

Lone orchid among the sea of sedges, forbs, and willows

In the past few years a few willow species (Salix discolor, S. eriocephala, and S. interior) have aggressively invaded and taken over the previously woody-free meadow.  This added competition combined with the stress from heat and drought of summers past had the prairie fringed orchids bloom much less vigorously than in previous seasons.  What two years ago was a profusion of blooming orchids, this section had only one flowering plant that I could locate.

E. Prairie Fringed Orchid (Platanthera leucophaea)

That being said there was still quite a few specimens in stupendous shape if you knew where to look.  Finding and enjoying their beauty pre-settlement wouldn't have been too hard a task throughout the fen and wet prairie regions of Ohio and the mid west/great lake states.  Being a life long fan of Big Ten football and basketball, I nicknamed this the "Big Ten orchid" for almost its entire geographical range occurring within states that are home to a conference's campus.

Closer look at their charming individual flowers

Within its wet prairie/meadow/marsh, fen, and shoreline habitats, prairie fringed orchid can grow upwards of four feet tall and contain well over 20 greenish-cream flowers spiraled around its stalk.  Each individual flower is about the size of a quarter and has its lower lip (labellum) deeply cut in a fringed fashion; almost as if the wind had shred and tattered tissue paper.  Their scent is light and faintly detectable by day but intensifies at night when its hawk and sphinx moth pollinators are most active and in the hunt for a nectar snack.

Handful of orchids peaking out above the sedges and grasses

I could witness these wondrous summer rarities every summer for the next 50 years and each meeting would be as precious and held dear as the last.  For your blogger nothing beats the sight of the prairie fringed orchids dancing in the warm summer breezes and their cream, waxy flowers gleaming in the sunlight.  There's little comparable to seeing their conspicuous wands contrasted against the surrounding green vegetation and brilliant sapphire sky.

A lovely pair of prairie fringed orchids

It may be hard to believe but the plant on the left in the photograph above could very well be older than I am. Fred Case, a brilliant botanist and master of North America's orchids recorded some plants eclipsing 30 years in age as an individual.  That's a lot of time, energy, and luck that has gone into an orchid that has evaded and escaped drought, flood, disease, browsing, and any kind of negative habitat change.  Just another reason to respect and appreciate these orchids not just for their looks but for their brawn as well.

E. Prairie Fringed Orchid (Platanthera leucophaea)

One of the more fun aspects to writing and publishing this blog is the opportunity to bring rare and unusual plants and habitats/ecosystems (like the prairie fringed orchid) home to those who cannot see or experience it for themselves.  I do my best to bring these topics and photos to life on your computer monitors and have you travel vicariously into the field with me; especially at sites and places as sensitive and secret as the prairie fringed orchids.

Orchid hiding alongside a spotted joe-pye weed (Eupatoriadelphus maculatus)

It really does seem like just the other day I was alongside these very orchids, admiring their physical charm and ghostly appearance like I am again a year later.  Even more difficult to believe is July is upon us again with so many more wonderful wildflowers and orchids to grace our landscape with their presence.  But you can't have July before you have the prairie fringed orchids knocking on the summer solstice's door once more...

Rare Plants in a Secret Prairie

This certainly isn't my first blog post to tell a tale of Adams county's ancient and mystical prairie openings and I can guarantee it won't be the last.  It's hard to stay away from such a diverse and engaging subject of Ohio's natural history and flora, especially when one spends a large amount of time combing its varying landscape.  Autumn is just as good a time as any during the growing season to visit the area's globally rare ecosystems and habitats, as they are still well alive with some of the year's last firework displays of wildflowers and tall warm-season grasses.  Come September I am always excited and anxious to pay a visit to one specific little prairie opening out of the hundreds of others to see one of Ohio's rarest vascular plants.

A particular Adams County limestone prairie with an elusive inhabitant 

At first glance this place doesn't seem to be anything different from the other countless dolomite-limestone barrens the county is widely famous for and you'd be right if you didn't know what to look for.  The rocky patches you see in the photograph above are not chunks of rock resting on the surface but rather exposed bedrock laid down over 400 million years ago during the Silurian age and known to geologists as Peebles-Dolomite.

Patch of exposed Peebles-Dolomite bedrock over 400 million years old

In many places the topsoil is only a few inches deep, making for very rugged conditions for any plant to grow in.  The soil is a type called rendzina, which is derived from weathered limestone bedrock and rich in humus, usually indicating an area that has been occupied by a grassland habitat for an extended period of time.  As time goes by and organic material builds up through decomposing plant matter, the soil becomes richer and comprised of more humus and less rock since the bedrock is slowly being covered and lost to the past.  Deep, rich soil is typical of mature forests that have had centuries, even millennia of leaf and herbaceous  decay but not so in these prairies where the organic soil layer is thin and bedrock still at the surface.  Despite the harsh reality of this environment, life has found a way to eek out an existence and cling to the shallow, rocky soil.  One of those survivors is the feature of this post and one of the most rare members of our flora.

Ear-leaved Foxglove  ~  Agalinis auriculata

Mixed in among the big bluestem (Andropogon gerardii), indian grass (Sorghastrum nutans), and little bluestem (Schizachyrium scoparium) lies the ear-leaved foxglove (Agalinis auriculata), a member of the figwort family (Scrophulariaceae).  A frequently used Latin synonym  for this species is Tomanthera auriculata.  Each September these plants grace this select prairie opening with their stunning pinkish-purple flowers for a couple weeks before slipping back into obscurity.

Ear-leaved Foxglove  ~  Agalinis auriculata

At first glance it's not hard to see the resemblance to other members of the Agalinis genus and its false-foxglove brethren.  The pink colored, five-lobed tube-like corollas appear in the leaf axils along the top of the stem.  Each flower only lasts a few hours before wilting and falling from the plant at the slightest touch or breeze. The buds break early in the morning and by noon are pollinated and have served their purpose for the day.  Each plant will bloom over the course of a week or so with a new set of flowers each morning until the ovary is fully fertilized and begins to mature.

Ear-leaved Foxglove  ~  Agalinis auriculata

Once pollinated the ovary quickly swells into a capsule tucked away inside the calyx and contains numerous small seeds.  The seeds mature quickly and are dispersed in late fall to over-winter and sprout in the spring.  Ear-leaved foxglove is an annual so seed production is a vital component to its continued existence and success; every plant, no matter the size, is the result of one season's growth and must complete its life cycle in that one  growing season.  A helpful trait this species has evolved to utilize is to be semi-parasitic on the roots of other nearby plants, most specifically asters (Symphyotrichum spp.).  The leaves are oppositely arranged and sessile with the upper leaves having two small lobes at the base where each leaf meets the stem.  These small lobes (auricles) or 'ears' are how the plant gets its common name ear-leaved foxglove and scientific epithet auriculata.

Ear-leaved Foxglove  ~  Agalinis auriculata

Due to being an annual, the plants put all their strength and energy into that one and only shot at flowering before giving up its ghost.  This leads to interesting results in the variation of size in flowering plants in a population.  I unfortunately caught these a bit late in the process this year and a large majority of the plants were already done and in seed but a few were still giving it one last go.  Some plants were eclipsing three feet in height and had multiple branching sections with dozens of seed pods on them while others, like this miniscule specimen above, were barely five inches tall with one bloom.

Distribution map of Agalinis auriculata (courtesy: BONAP)

The relic prairie I was standing in was just one of a handful of populations left of the ear-leaved foxglove in the state of Ohio.  The few others are well-kept secrets and scattered around the nearby area in other similar barren situations.  The original range for this species in Ohio was slim and scattered to begin with with the only records coming from Adams, Butler, Muskingnum, and Ottawa counties.  For decades the species was considered extirpated from the state and feared gone forever until a chance re-discovery in an Adams county prairie in 1985.  It had sat in the seed bank for an unknown amount of time before the right environmental conditions allowed germination.  Despite additional searching in Ottawa county, the species remains only extant in that handful of Adams county populations.  All the currently extant locations seem to be associated in one way or another with recent disturbance to the habitat, which is known to help stimulate the seed bank and allow this plant to spring forth.  Sometimes mankind's activities can have positive effects, even on something so rare as Agalinis auriculata.

Looking at the overall distribution and range of the species above shows a clustering in the 'breadbasket' region of the United States and outlying scatterings throughout the Midwest and south-central states.  Despite a good showing of records in those heartland states, many, actually most, of those counties no longer contain any existing populations of the ear-leaved foxglove.  Its affinity for mesic, rich, black-soiled tall grass prairies spelled its own doom when they were tilled and plowed for agriculture.  Today the ear-leaved foxglove is only found in about half of its original range with a majority of the remaining populations at the center of its distribution in Illinois, Iowa, and Missouri.  In response to its rarity and disappearing habitat due to succession and development/agriculture, this species is currently under consideration for federal listing.

Ear-leaved Foxglove  ~  Agalinis auriculata

There's something sentimental about being in the presence of something so beautiful and sparse.  It gives you a better appreciation for its existence and place in the natural landscape of these already special and rare ecosystems.  Apart from being the rarest denizen of this particular dolomite prairie, it was certainly not the only uncommon or charming plant to be found.  This next one is not only stimulating to the eyes but to the olfactories as well and can be found if you follow your nose...

Great Plains Ladies-tresses  ~  Spiranthes magnicamporum

I've shared the great plains ladies'-tresses (Spiranthes magnicamporum) on here before and it would seem rude to leave them out here when they are growing just a few feet away from the ear-leaved foxgloves and blooming concurrently.  As mentioned above, the odor emitted from these small crystalline flowers is deliciously sweet and refreshing and well worth a whiff.  It's not uncommon to smell these before you see them on a warm fall afternoon.

Great Plains Ladies-tresses  ~  Spiranthes magnicamporum 

One of the last species of orchid to bloom in the state, these plants are right at home in the xeric and calcareous thin soils of the dolomite prairies.  Spiranthes magnicamporum was once lumped as a variety of the infamously difficult Spiranthes cernua  complex.  In-depth research into its genetics, habitat, and phenology in the mid 1970's allowed the species to be rightfully elevated to full species status.  Its later blooming period, yellow-colored throat, strong fragrance, and dry, limestone habitat preference help separate it from the similar multiple forms of S. cernua.

Great Plains Ladies-tresses  ~  Spiranthes magnicamporum

A closer inspection of the individual inflorescences shows the lateral sepals flared away from the sides and raised just a bit above and seem to imitate the look of a charging bull.  The great plains ladies'-tresses begin to bloom in mid-September and are known to flower through October and into November after even the asters and goldenrods have called it a year.  It's hard to look at one of the last, if not the last, of the orchids to bloom and say goodbye.  For someone as passionately obsessed with that family as your blogger it's a bittersweet moment.

Great Plains Ladies-tresses  ~  Spiranthes magnicamporum

As I picked myself up off the ground from my low and close-up encounter with the great plains ladies'-tresses and dusted myself with crossed fingers the notorious chigger mites hadn't gotten me too bad, I took a look around the rest of the prairie and noticed some of the other interesting flora the habitat had to offer.  One of those quick to catch the eye was one of Ohio's only native succulent plants.

False Aloe  ~  Manfreda virginica

The fleshy, aloe-like leaves of the appropriately named false aloe (Manfreda virginica) are perfectly adapted to the dry and rough conditions of the drought-like barrens.  The tall flowering stalks waved in the breeze three to four feet above the leaves with their marble-sized seed pods turning black with maturation.  They flowered months ago in the heat and humidity of July and only have their unique leaves to show off come fall.

Rough Blazing Star  ~  Liatris aspera

Normally a well-welcomed and loved late wildflower, the rough blazing star (Liatris aspera) can become a potential downer when it's easily confused with the ear-leaved foxglove as you approach and gaze out into the grasses.  Other than the similar pink color to the flowers there's not much else to confuse the two with once getting closer to the plant.  I love all our native Liatris species but this one may be my favorite of them all.

Prairie Brome  ~  Bromus kalmii

Perhaps not the showiest or most noticeable of the plants there, the prairie brome (Bromus kalmii) deserves a closer look if for anything to see the fascinating wooly pubescence on the fruiting heads (spikelets).  Switching to the macro lens and focusing in on the lemmas and glumes reveals the interesting pattern and made for an artistic shot that turned out pretty well in my opinion.  Prairie brome is an uncommon species in Ohio and is at the southern fringe of its natural range, especially as far south as Adams county.

Prairie Orange Coneflower  ~  Rudbeckia fulgida var. fulgida

Despite peaking a couple months back in late July and early August, the prairie orange coneflower (Rudbeckia fulgida var. fulgida) was still holding on in pockets throughout the xeric landscape.  The small, deep-orange flower heads really add a spark of color and contrast to the light yellows and greens of the dominating grasses.  I look forward to publishing a post on all of Ohio's native Rudbeckia species in the near future.  They are one of my favorite genera of plants and are still a bit of a taxonomic mess.

Gray Goldenrod  ~  Solidago nemoralis

Probably the most common non-graminoid plant in the barrens was the gray goldenrod (Solidago nemoralis), a frequent and widespread species throughout the state in all sorts of dry soil situations.  It has the typical and classic goldenrod look but can be told apart relatively easily unlike a number of species.  It's short stature and unbranched,  wand-like appearance combined with a very pubescent grayish-red stem help with an ID.

With fall's climax fast approaching a gradual slip into the dull browns and grays of winter in the inevitable future I'm enjoying every second I can spend out in the field in the midst of the season's last botanical beauties and friends I won't be seeing for quite some time.  It's hard to believe another growing season is coming to an end; I swear I was admiring trillium and Virginia bluebells just the other day...

Purple Passionflower (Passiflora incarnata)

Ohio is home to just under 1,800 native species of vascular plants according to the latest published list of the flora.  I've seen my fair share of those on that list; some are rather forgettable and not very showy, while some are 'in your face' gorgeous and are impossible to ignore.  This is the latter.

Purple Passionflower  ~  Passiflora incarnata

Few wildflowers can draw the eyes of even the most unobservant or uninterested as easily as the purple passionflower (Passiflora incarnata).  You wouldn't be wrong to assume its home is the steamy tropics near the equator; most members of the Passiflora  genus are native to tropical areas and have an equatorial distribution.  However, this species is right at home in the southeastern section of the country and even makes it into extreme southern Ohio.  Many are probably most familiar with this passionflower in the garden and/or cultivation scene but it does exist within the state naturally, albeit quite infrequently.

Purple Passionflower  ~  Passiflora incarnata

Passiflora incarnata is a threatened species in our state, where indigenous populations have almost entirely been recorded in the southernmost counties along the Ohio River.  Despite being a 'weed' in the south, the extended frost/freeze windows to the north help limit it at its northern distribution terminus.  This past weekend while botanizing Hamilton county and feasting on the paw paw's I posted about recently, I came across an entanglement of this enchanting vine along the side of the road.  This species thrives in disturbed areas with full sun such as; fields, thickets, and roadsides.

Purple Passionflower  ~  Passiflora incarnata

Although a vine, the plants themselves are herbaceous, not woody, and all above-ground growth is killed back each year after the first freeze but will return from the underground perennial root stock come spring.  The side profile photo above really exhibits this plant's remarkably unique architecture and composition.  There truly is nothing else outside another Passiflora that comes close to its intoxicating beauty.  Come fall the plant is dotted with large, edible fruit pods know as 'passion fruit'.  I've never had it but many find the sweet, gummy flesh surrounding the seeds to be delicious.

You may be interested to know that there's a second species of passionflower native to Ohio's soils and is more common and wide-spread than the former but not nearly as large or noticeable.

Yellow Passionflower  ~  Passiflora lutea

The yellow passionflower (P. lutea) is structurally more-or-less the same as the purple taxa above and is instantly recognized as a member of Passiflora.  They are about one-third the size of the purple passionflower but still show off their charm and beauty when the environmental conditions allow.  Ohio still lies at the northern fringe of its range but the yellow passionflower can be found in thickets, rocky woods, and even low, rich woods throughout the southern half of the state.

Fate and a Tiny Orchid

A few summers ago I headed out on a seemingly routine hike through one of my favorite areas of Zaleski state forest in Athens county.  Comprised of nearly 27,000 acres, Zaleski is choked full of interesting habitats and flora with a few hidden rarities and surprises within its borders.  The particular spot I decided to explore is a nameless, deep hollow that branches off from a small stream valley and splits two parallel-running ridges; each with its own unique plant communities and diverse species compositions.  I opted to follow a lightly-worn deer path along the upper slopes of the southwest-facing ridge to scout out what summer wildflowers were in bloom and perhaps come across something new.  I'd walked the same expanse of mature deciduous forest many times before and had quickly grown to appreciate and love its undisturbed appearance and peaceful atmosphere.

I slowly weaved my way through the mixed forest of chestnut, black and white oaks, sourwood, serviceberry, and red maple; keeping my eyes carefully peeled for anything out of the ordinary.  The ground was covered in a surprisingly rich mosaic of vegetation accustomed to the xeric and acidic underlying soils.  Reindeer lichen and an assortment of moss species carpeted the ground, cushioning my light footsteps as they fell.  The waning late-afternoon sun filtered through the canopy and dappled the forest floor in intense beams of warm light.  Not even the thick air, heavy with humidity could spoil the tranquility of the place.

I eventually came to notice that one of my boot laces had come undone sometime during the hike and decided to stop and take care of the matter.  I slide my camera equipment off my back and knelt down to re-tie the laces when out of my peripheral vision I noticed an intriguing sprig of green growing  a few feet away in a large patch of moss just at the edge of the rock ledge.  It was quite small, only four or five inches in height but different enough to have caught my eye.  I leaned in closer and with a shocked smile realized I had made quite the fateful discovery.

Green Adder's-Mouth Orchid  -  Malaxis unifolia

That little green sprig turned out to be the relatively rare and minuscule green adder's-mouth orchid (Malaxis unifolia).  I sat back in disbelief at the randomness of the find and couldn't help but ponder the odds of choosing that very spot and moment to fix my laces.  These orchids are already notoriously hard enough to see and locate under the darkened canopy and overgrown ground cover in its early July woodland home, let alone their green color and miniature size.  Not the best of combinations for discovery but the increasing difficulty makes it all the more exciting!

Green Adder's-Mouth Orchid  -  Malaxis unifolia

It may come as little surprise then that this particular orchid is listed as potentially-threatened in Ohio with a limited number of collections and populations throughout the eastern half of the state.  I suspect it could be a lot more common and frequent than current records or knowledge indicates, considering its preferred habitat of dry, acidic mixed deciduous forest is readily available in our state.  Add in its tiny stature, color, and odd blooming time and you have the perfect set up for a vastly overlooked plant.

Each plant rises from a fleshy subterranean corm and produces a single stem topped with a raceme made up of dozens of puny inflorescences gradually maturing and elongating from the terminal cluster.  The scientific epithet of uniflora refers to the single leaf that sheathes the lower half of the stalk.  Despite the numerous individual flowers each plant produces, typically only one or two are successfully pollinated and quickly swell with microscopic seeds.  Looking at the photograph above you can see a single maturing capsule located  along the middle left side of the raceme.

Green Adder's-Mouth Orchid  -  Malaxis unifolia

The green adder's-mouth orchid has the distinction of being Ohio's smallest indigenous species of orchid (in terms of flower size) but that doesn't necessarily translate into little worth or interest.  I find it to be a rather charming and refined species of plant that few are lucky enough to lay eyes on and appreciate first hand.  Next time any of you reading this are hiking in the eastern half of Ohio and find yourself in a dry, acidic mixed oak or upland woods during the mid-summer months keep an eye out for this orchid.  You never know what you may luck into.

In the summers following my initial stumble onto this lone specimen of orchid I have journeyed back each year to get reacquainted with it and spend some more time admiring its unique design and appearance.  I'm happy to report this has been the fourth year in a row it has broken ground and flowered in the same exact spot as year's past.  With a bit of luck this little guy will be around to greet me as an old friend for many summers to come and I can enjoy its company under the mighty oaks and reminisce of our fateful chance encounter on that hot and muggy afternoon in early July...