Friday, May 24, 2013

Hybrid Lady's Slippers at Castalia Prairie

I'm back to follow through on my promise to bring you the last chapter of this past weekend's northwest Ohio botanical foray.  I've shared the exceptional lakeside daises and you've seen the electric display of wild lupine but I feel like I've saved the best for last.  I hinted at the topic for this concluding post and if you are even a semi-regular reader of this blog, I don't think it was too hard to surmise the subject matter would be orchids!

Castalia prairie within Resthaven Wildlife Area

Not far inland from the shores of Sandusky Bay on Lake Erie is Resthaven Wildlife Area in Erie county.  Within the 2,000+ acres of wildlife area lies Castalia prairie: an old, intact prairie remnant that has long been home to the largest population of one of Ohio's rarest plants.  The slightly mucky black soil sits over a deposit of marl and tufa (a porous variety of limestone) with upwelling groundwater that helps to keep the site moist throughout the year.  This combination of calcareous soils and alkaline groundwater is what allows this great rarity to persist and thrive in such great numbers.

Clump of small white lady's slippers (Cypripedium candidum)

That plant is none other than the state-endangered small white lady's slippers (Cypripedium candidum), which occur literally by the thousands throughout the prairie.  Early settlers wrote of coming across large swathes of grassland come mid-late May in this area of the country and the air being saturated with the sweet scent of this orchid as countless thousands bloomed in the prairies.  Those sights and smells are long gone in today's world due to habitat loss and alteration but Castalia gives as close a glimpse (and whiff) as one can get here in Ohio.

Small white lady's slippers
Very rare double-flowered specimen

It was certainly something incredible in and of itself to see so much of this dainty orchid coming into bloom and peaking their heads out of the previous year's dead growth on the ground below.  Having only seen these by the handful in select limestone barrens in extreme southern Ohio, I was speechless at their grandeur and appearance at Castalia.  However, believe it or not it wasn't the small white ladies I had specifically come to see.  No, there was something more elusive hiding among the dead grasses that my eye was anxiously hoping to catch a glimpse of.

A suspicious and odd-looking lady's slipper orchid

What I was looking for were lady's slippers with a hint of yellow to their lip and/or dark sepals that signaled the presence of crossed genes between two different species.  That's right, a hybrid lady's slipper and orchid I had wasted many an hour daydreaming of finally make acquaintances with.

Andrew's lady's slipper
Andrew's lady's slipper just waking up

It wasn't too long before I fortuned upon a particularly suspicious specimen that showed the distinct yellowish labellum and slightly darker sepals of my bounty.  Now, don't let the name fool you;  Andrew's lady's slipper (Cypripedium x andrewsii) is not named after your blogger but in honor of Edwards Andrews, the original discoverer of the hybrid.

Andrew's lady's slipper next to small white lady's slipper

Additionally, I spotted a newly opened hybrid lady's slipper growing right alongside one of its parent species, the small white lady's slipper.  Despite finding examples of orchids clearly showing a mixture of genes, I still wasn't fully satisfied and was holding out hope a better specimen would present itself.  Luckily, my good friend and eagle-eyed companion Dr. Todd Crail of the University of Toledo came through!

Excellent specimen of Andrew's lady's slipper (C.x andrewsii)

Now that's more like it!  This sole plant was easily the best one found all day and in perfect bloom to boot; a very well-timed thing as these orchids don't last long at all in prime shape and color.  Here you can see the perfect combination of its two parent's traits which I will now get into in more detail.

small white lady's slipper (L), Andrew's lady's slipper (M), small yellow lady's slipper (R) 

I quickly put together the above photo in an attempt to best show the similarities and differences found in the hybrid orchids scattered throughout the prairie opening.  On the left is one of its parents, the aforementioned small white lady's slipper; while on the right is the other parent species, the northern small yellow lady's slipper (C. parviflorum var. makasin).  With both parent species to either side it becomes more apparent and easy to see that the hybrid largely kept the white color of the small white's pouch with some very faint yellow tinging blended in.  The sepals are a much darker color hailing from the small yellow lady's slipper and overpower the more light greenish-brown sepals of the small white.

Phenomenally spotted pattern to the hybrid's labellum

What I found most attractive and noticeable about this particularly well-blended specimen was the liberal spattering of magenta dots throughout the inside, rim, and outer surface of the labellum.  There's just nothing like getting a closer look at the pouch with this kind of artistic detail; it's absolutely stunning!

Andrew's lady's slipper (C. x andrewsii)

While the small whites were just about everywhere throughout the section of Castalia, the true-blue (or should I say yellow) northern small yellow ladies (C. parviflorum var. makasin) disappeared from the prairie years ago due to what is/was believed to be a change in the hydrology of their location(s).  Present or not now, it's clear their genetics cling to existence within the previously shared photographs of Andrew's lady's slipper.  In fact, many of the small whites exhibited the ever-so-slightest traits of the small yellows somewhere on the plant.  Very few of them appeared to be pure C. candidum.

Hybrid lady's slipper
Hybrid lady's slipper

In the end, Todd and I found about a dozen or so lady's slippers that showed strong/obvious signs of crossing between the small whites and yellows out of the thousands of orchids at the site.  These pictures above came across to me as mostly C. candidum except for the clearly yellow tinge to the pouch and maybe slightly darker sepals.  

For those that enjoy the nitty-gritty taxonomy aspect to plants, this specific hybrid is called Cypripedium andrewsii var. andrewii for its cross with the small yellow lady's slipper.  This variety typically exhibits a specimen closer to the one shown just a bit above with a mostly white pouch and very dark sepals.  In other situations the small whites have been known to occur near enough some large yellow lady's slipper (C. pubescens) to create the other variety C. andrewsii var. flavillianum.  This species is less attractive than the other with larger flowers, light yellow labellum with no magenta spotting, and coffee brown sepals.

More yellowish hybrid 
Perfect Andrew's lady's slipper hybrid specimen

After spending nearly four hours in the prairie searching out and photographing these unique beauties and acquiring quite the sunburn on my forearms we decided to call it quits and make for the car.  It was a very satisfying feeling walking back knowing I had another Ohio orchid on my memory card and check marked off the list.  Of the 48 Ohio native orchids I count on my list, I have now seen 45!  Only three more to go and with any luck I should be down to just ONE at the end of this year.  It's crazy to think one of my major botanical bucket lists is nearing completion but that's hardly the end of the story.  I have my fingers crossed a book would be soon to follow; it's just getting those pesky photographs down first and then finding the time to write and plan it out.

I sincerely hope you enjoyed this late-spring swing through some of the botanical hot spots of northwestern Ohio and will tune back in soon as I continue to bring you more of the natural treasures of Ohio!


  1. I just love looking for orchids with you, Andrew! Your excitement is exhilarating, and your luck (skill?) in finding the most elusive is just amazing. Looking forward now to finding Small Yellow Lady's Slippers with you in Vermont next week.

  2. Those are spectacular, Andrew. Glad you gave some scale in those last pictures since it is hard to see otherwise how tiny these are. Fabulous find and fabulous photos. We are off this week to see one of the few locations for Cyp. parviflorum in the state and to see the Eastern Fairy Slippers which are now blooming on the other side of the mountains.

  3. Nice going Andrew in locating this hybrid. I searched hard for C. x andrewsii among hundreds of C. candidum and a dozen C. parviflorum var. makasin at a nearby fen a few days ago. No luck. I can't understand why the hybrid is not there, though I found a few with traces of back crossing last year. Excellent blog post in explaining the hybrid, by the way.

  4. Excellent presentation! I love this blog entry... You had some really great luck out in the field this year. Hope you get your "48" before the end of the season.

    Jim Fowler, Greenville, SC