Buffalo Clover Re-discovered 100 Years Later

Let's travel back to 1910 when famed botanist and ecologist E. Lucy Braun was roaming and traversing the forested hills of Hamilton county, Ohio, collecting and observing the native flora to gain a better understanding of the fascinating and seemingly endless diversity and ecosystems of the extreme southwestern corner of our great state.  Lucy was well before her time and one of the most accomplished and talented botanists Ohio ever produced; let alone the fact she was a woman in a largely male-dominated field.  Her findings, knowledge and publications are still widely used and appreciated today by anyone with an interest in the botanical world.  

On one particular day in May of that same year she came across an intriguing and very rare species of plant with clusters of pale-pink flowers and three-parted leaves that she collected and sent to the herbarium at the University of Cincinnati.  There the voucher sat for decades on end as the only proof that buffalo clover (Triflolium reflexum) ever existed in Hamilton county and it slipped into legend and mystery.

Dan Boone and one of his greatest discoveries, the Buffalo Clover (T. reflexum)

Fast forward a little over a century later and another great native of the area and incredible botanical mind would erase that mystery and legend.  On an early May afternoon while wandering around the same area as Lucy over 100 years earlier the sharp, eagle-eyes of Dan Boone spotted something unique growing in small groupings under a mixed oak canopy that made his heart skip a beat.  If there was anyone in Ohio worthy and deserving enough to find something of this botanical magnitude it's Dan.  You don't get a nickname like 'the clover kid' for nothing!  Our native clovers (Trifolium spp.) have long been one of Dan's greatest and deepest passions and finding this great rarity in his home county just mere miles from his house was more than a dream come true.  I can still hear the excitement in his voice as I got the call sharing the news and an invitation to come down and photograph the gorgeous specimens.

Buffalo Clover (Trifolium reflexum)

While Lucy described her plants as having pale pink flowers, these plants exhibited more of a cream color with perhaps the slightest tinge of pink on newly-opened corollas.  Not to be confused with Ohio's other native species of clover, the Running Buffalo Clover (T. stoloniferum); this species lacks the running stolons.  The length of the calyx teeth can also be used to distinguish the buffalo clover from other non-native and introduced Trifoliums but once you see these remarkable plants in person it's hard to mistake them for anything else.  The flower heads are significantly larger than the European white clover (T. repens) as are the running buffalo clover's as well.

Buffalo Clover (Trifolium reflexum)

Buffalo clover has the interesting trait of being an incredibly variable species from population to population.  In fact, Dan has seen a number of populations throughout the Midwest and no two have ever been the 'same' in appearance.  Sometimes the leaves will exhibit chevrons, or watermarks, on the leaves while others (such as these in Hamilton Co.) will lack them completely.  The color of the inflorescence can greatly differ as well, from scarlet red to creamy white to pink and light yellow.

The two photographs above are both buffalo clover from a recently re-discovered population in Mammoth Cave National Park Dan and I saw last early June down in Kentucky.  Notice how the blooms are deep red and the smaller leaves show off the chevrons that the Hamilton county population lacks.  Some suggest there are a great number of varieties within the species but that has yet to be confirmed or denied through genetic work.

Buffalo Clover (Trifolium reflexum)

I was fortunate to catch the plants in peak bloom a couple weeks ago as I made the journey from Athens to Cincinnati to photograph and document this remarkable find of Dan's.  I've seen many rare and incredible species of plants in my countless wanderings and botanical forays with Dan but few could ever match the emotion and excitement of seeing this historic species on Ohio soil.  Some may shrug their shoulders and say "so what, I see 'white' clover in my yard every day", but how wrong they are to even suggest this plant is in the same category as the exotic species of Europe and Northern Africa.  This truly is one of Ohio's most rare and imperiled of plants.

Trifolium reflexum distribution map (courtesy of BONAP)

Originally found and documented in about a dozen scattered Ohio counties, it's numbers and populations have dwindled in the last century.  East of the Mississippi River the buffalo clover becomes increasingly rarer with scattered and isolated populations throughout the Midwest and southeastern states.  As you can see from the distribution map above, the only area of the country where it is rather common is in Missouri and Arkansas, where it is a frequent species of the Ozarks.

For the past few decades the only population still extant in the state lied in Pike county where the plants bloomed scarlet red and exhibited faint chevrons on the leaves; much like the previously pictured buffalo clover from Mammoth Cave.  Thanks to Dan's constant vigilance and efforts Ohio can now proudly claim back another population to its records.  The fight is far from over though, as this species is an annual and relies heavily on seed production and disturbance to fight back encroaching vegetation and over-shading.  I'm curious what effects an under story burn would produce at the new Hamilton county site as this species has historically responded very well to burns.  In fact, the plants at Mammoth Cave had sat dormant for nearly two decades in the seed bank of a rocky, dry mixed oak forest before a prescribed burn a couple spring ago sprang them forth.

Buffalo Clover (Trifolium reflexum)

Upon closer inspection it becomes evident just how attractive and gorgeous a flower head this species can produce.  The individual inflorescences bloom for a short time before reflexing and all hang down below the long pedicle that supports the head.  This picture also shows the long calyx teeth (the thin, green 'threads' at the base of each individual flower) which helps distinguish this species.

Buffalo Clover (Trifolium reflexum)

This particular population was growing in a relatively open area in the under story of a mixed oak woodland with white, red and chinkapin oaks and a scattering of sugar maple along with an herbacious association of yellow pimpernel (Taenidia integerrima), great yellow woodsorrel (Oxalis grandis), and Bosc's Panicgrass (Dichanthelium boscii).  Further up the slope the under story becomes much more thick with vegetation but luckily the immediate area seems to be relatively free of the intensely invasive Asian Amur bush honeysuckle (Lonicera maackii).  Buffalo clover occurs in rocky, open woods and prairies with a strong preference for acidic soils.  Perhaps the acidity of the soil is a distinguishing factor in the color of the resulting flowers?

Buffalo Clover (Trifolium reflexum)

After photographing and admiring the remarkable buffalo clover for quite some time we decided to do something that I dare say very, very few have ever (and I do mean ever) had the chance of becoming a part of.  Hamilton county, Ohio has the very rare honor of being one of the only counties in the world where one can see both the native buffalo clover (T. reflexum) and the federally endangered running buffalo clover (T. stoloniferum). I can't say without any real assurance but it just may be the only county currently known to have both species with extant populations.  These are Ohio's only two indigenous clovers and both are listed as endangered in our state.

Running Buffalo Clover (Trifolium stoloniferum)

Not long after leaving the buffalo clover my eyes rested upon our other native taxa and equally gorgeous running buffalo clover (T. stoloniferum).  I felt a sense of honor and accomplishment to have been in the presence of two of Ohio's most rare species.  I really would like to find out just how many other counties in the country can lay claim to both these native clovers within their borders.  Perhaps Hamilton is unique in that fact but time will tell and while I am proud of that fact I do hope others can and will eventually share in the joy; the more of these beautiful plants there are, the better off our natural diversity is!

Running Buffalo Clover, Orchids and a Native Honeysuckle, Oh My!

Hamilton county, Ohio is home to some of the rarest and most interesting of all our flora.  Being so far to the south with its rolling, forested hills overlooking the mighty Ohio River, it's not hard to imagine the diversity and beauty on display in late spring.  Personal friend and botanist extraordinaire Dan Boone was kind enough to accompany me on our hike around the county to see what interesting flora we could find!

Lonicera sempervirens

Lonicera sempervirens

First up is one of Ohio's own native species of Lonicera or Honeysuckle.  It's sad that in today's Ohio the genus Lonicera and names like 'Honeysuckle' conjure up feelings of hatred and resentment if even for good reason.  While the non-native and grossly invasive Asian species are clogging our forests and woodlands with their monoculture creating terror, our native species, such as the above pictured Trumpet Honeysuckle (L. sempervirens), are losing habitat and their rightful chance to show off some color.  When not in bloom, these very inconspicuous vines are hard to pick out from the sea of surrounding green but when you catch them at the right time as we did today it's nigh on impossible to not be stopped in your tracks at their stunning beauty.  Some botanists and ecologists will argue that this species is not truly indigenous to Ohio and all populations are simply landscaped cultivation escapees but I strongly disagree with that stance.  Scattered irregularly throughout the state, many instances may in fact be escapees but it's my opinion that we definitely have naturally occurring populations.  This species is known from the depths of Shawnee State Forest in Scioto County, far away from any locations of civilization/cultivation.  Several years ago a severe winter ice storm downed many trees in Shawnee, creating numerous openings and clearings throughout the forest.  Come spring some of these openings exhibited a strongly increased showing of this plant in bloom.  It's clear L. sempervirens had been biding its time in the seed bank until nature created the necessary disturbance for it to make a comeback.  How long these seeds remained viable in their patient gamble for sunlight who knows but it all strongly points to this plant naturally occurring in Shawnee without any human intervention.  Not to mention most of the cultivated varieties I've seen of this plant do not so strongly resemble those of the wild blooming plants.

Corallorhiza wisteriana

Corallorhiza wisteriana

Growing unknown to almost all who walk past it in its cloak of secrecy is the Spring Coral-root orchid (Corallorhiza wisteriana).  Typically Ohio's earliest blooming Corallorhiza orchid, this diminutive saprophytic orchid has no chlorophyll (no 'green' parts to these plants) and thus is unable to produce its food via photosynthesis.  Instead it uses its vital symbiotic relationship with mycorrhizae fungi in the soil to help derive its nourishment from decaying organic material.  Usually less than a foot tall and brown colored, you can imagine the depth of difficulty it can take to find this plant growing out of the leaf litter in well-drained, upland forest communities.  This specific plant was found growing in a fantastic representation of a southwestern Ohio Oak/Hickory forest on its lower, mesic slopes.

Corallorhiza wisteriana

While the Corallorhiza genus of orchids may not hold a candle to the previously showcased Cypripedium's for most people, I think they are stunning and beautiful in their own right.  Take a close look at those snow white lips adorned with a peppering of brilliant magenta spots.  This plants chasmogamous flowers may only be a few millimeters wide in size but they more than make up for their tiny size in their splendid display of color.

Ray (front) and Dan (back) admiring the T. stoloniferum in the forest opening

I was certainly impressed and overjoyed at getting these two rare and beautiful specimens on my species list for 2011 as well as on the camera's memory card but it was time to make for a small opening/path in the woods that provided the suitable habitat for one of Ohio's and the United States rarest species of vascular plants, the Running Buffalo Clover (Trofolium stoloniferum).  Currently listed as endangered on Ohio's rare plants list as well as Federally endangered, this plant has an incredible story to go along with its visually stunning floral displays (at least I think so!).

Initially described to the scientific world and community back in the early 1800's, this plant quickly waned in numbers as the century closed out and by the middle of the 20th century it was considered extinct.  A sad end to such an incredible species tied to our part of the country's natural history.  Then, out of nowhere in 1985 two populations were found in West Virginia, igniting a fire under the behinds of botanists throughout the Midwest in a race to find more extant populations in the Running Buffalo Clover's original range.  Since that initial rediscovery in 1985, five of the eight states formally known to harbor this species can proudly claim naturally occurring populations.  West Virginia, Ohio, Indiana, Kentucky and Missouri are the lucky five, while Illinois, Arkansas and Kansas are still searching for their lucky break.

Trifolium stoloniferum

Trifolium stoloniferum

The clovers habitat requirements of moist, fertile soils in regularly disturbed deciduous forests with partial filtering sunlight give the impression that this species would exist in much higher numbers since this habitat exists with reasonable occurrences throughout southwestern Ohio today.  Unlike many other rare and endangered plants that need undisturbed, mature habitat, Trifolium stoloniferum relies on long-term disturbance of moderate proportions such as mowing, grazing and foot traffic.  Oddly enough this species preferred habitat was not nearly as frequent and common in the primeval Midwest environment and relied on the time periods mega-fauna,  most notably the North American Bison as well as the Native Americans to artificially create its grassy woodland openings.  In pre-settlement times this species was probably found most commonly along the natural Bison and Indian trails as well as along the margins of woodlands and prairies.  Once the Bison were hunted to near extinction this species vital relationship with the massive quadrupeds ceased to exist and followed its necessary counterpart down the road of oblivion.  Due to T. stoloniferum's seasonal need for disturbance, proper landscape and habitat management is critical in keeping this plant around for years to come.  Without management, its forested gaps and openings would quickly fill in.  Unable to survive the dense shade of the forest, the Running Buffalo Clover would quickly meet its unfortunate fate.

Trifolium stoloniferum

Trifolium stoloniferum

For most people a clover, is a clover, is a clover and how to tell them apart is wasted words on their ears.  Fortunately, Trifolium stoloniferum is one of the easiest of the clovers to I.D. and has a couple key distinguishing characteristics.  The flower head (which is made up of many, small pea-like inflorescences) sits atop vertical, unbranching stalks that are adorned with a pair of three-parted leaflets oppositely arranged on the stalk an inch or two down from the flower head.  No other Ohio clover, native or introduced, has this 'platform' of leaves sitting directly below the flowers.  This plant is also notoriously stoloniferous, meaning it has stolons or long 'runners' that spread out and extend from the base of the plants stems.  These runners are able to take root and help continue the propagation and growth of a small population.  The leaflets also lack the common Trifolium arrow-shaped 'watermark'.  Taking a look at the individual flowers reveals the delicate beauty of the all-white inflorescence tinged with purple.  Just your average, yard clogging clover?  Hardly!

Trifolium stoloniferum leaves

Imagine finding a four-leaved clover leaf to this Federal endangered rarity.  Now that is what I would call good luck if there ever was some!  I can't thank Dan enough for sharing the location of this spectacular little patch of Running Buffalo Clover nestled in a random woodland opening.  I've had this species high on my 'life list' for a while and to finally mark it off brought one heckuva smile to my face!  Now to search out Ohio's only other native species of Trifolium, simply called the Buffalo Clover (Trifolium reflexum) that is likewise endangered in our state.  Call me crazy, call me a weirdo but who would have thought a species of Clover would get me this excited.  I found it very fitting that today was National Endangered Species day (the third Friday in May) and I celebrated the most proper way imaginable with a visit to one of Ohio's and the United States endangered species!