Sunday, June 15, 2014

Gone Boggin' in Southeast Michigan

There are few habitats I love to explore and delve into more than the peaty goodness that is a sphagnum bog. These heavily acidic and nutrient poor habitats are home to a seemingly endless parade of rare and unusual plant species that thrive in the otherwise harsh and unforgiving conditions.  Orchids, carnivorous plants, sedges, and Ericaceous (plants in the heath or Ericaceae family) species are just the beginning of what you may find in the depths of any high-quality bog.

This past weekend I managed to get out and get my feet wet in one of these fantastic places in southeast Michigan with a few good friends and very knowledgeable naturalists in Todd Crail and Bill and Deb Marsh.  Deb happens to be a fellow nature blogger and I encourage you to check out her work by following this link HERE.  It was an all day jaunt through a diverse array of rare and undisturbed habitats apart from the bog and I will be bringing those places to you in the next post.  For now it's time to slip into some rubber boots and avoid the poison sumac as we wade on into a squishy sphagnum paradise.

Flush of green on the floating bog mat

While nearly all of Ohio's peatlands have been lost to the past due to the forces of natural succession, draining, and mining, the same cannot quite be said for our northern neighbors in Michigan.  Many of their bogs have met the same fate as ours but enough remain to represent their kind in a proud fashion.  Sphagnum bogs owe their existence to the massive sheets of ice that once covered the area tens of thousands of years ago during the last ice age.  When the ice began to recede north, immense chunks were shed and left to melt atop the freshly deposited till in the wake of the glaciers.  As those deposited ice blocks melted, they left cool, clear pools of water on the barren, rock strewn surface known as kettle ponds.

Initially sterile and lifeless, the kettle ponds quickly began to support plant life on their margins and over the millennia accumulate enough sphagnum moss and dead plant matter to create floating vegetation mats atop the cold water that harbor the diverse array of specialized plant life we see today.  Given enough time these floating bog mats eventually grow to cover the entire surface of the kettle ponds and give rise to trees and shrubs before eventually filling in completely to form swamp forest.  Standing in the muck and swatting mosquitoes under a mature canopy of swamp white oak, red maple, and black ash today would hardly make you think about being over what used to be open water thousands of years ago.

Lucky for us, the bog we visited was far from its fate of reverting back to a forested climax community and was full of all the rare and exciting flora one would expect to see in such a high-quality example.  Luckier still was our timing happened to coincide with the blooming of one of the bog's most spectacular and rare residents in the timeless dragon's mouth orchid (Arethusa bulbosa).

Dragon's Mouth Orchid (Arethusa bulbosa)

Of the nearly 70 species of wild orchids I've encountered in my travels and forays thus far, few if any compare to the mythical appearance and beauty of this orchid.  The magnificent flush of magenta set against the rich greens and yellows of the surrounding bog make this wildflower impossible to overlook and scream out for attention.

A pair of the mythical Arethusa

This delicate wonder is an extremely rare species back here in Ohio, with only one extant site known in a bog in the northeastern part of the state.  There was easily more Arethusa in this one bog in southeastern Michigan than what's left in the entire state of Ohio, which is a sad reality to be sure but beggars can't be choosers and I'm for one thankful we can still claim to have this voluptuous wildflower around.

Dragon's mouth orchid among the poison sumac

Arethusa is one of the most classic orchids of the boreal north and its plentiful sphagnum bog habitat where in some places it comes up like a weed and can turn entire fields of sphagnum bright pink in the early summer.  It typically occurs in the wettest and sunniest parts of any bog and with its fickle personality will quickly disappear if shade and/or a change in the hydrology become permanent fixtures.  There are many common names of plants that make you scratch your head in confusion but this species' name hits the nail on the head as it does invoke visions of dragons and other mythical beasts.  Its genus name of Arethusa is after a beautiful Greek water nymph of the same name.

Arethusa in situ in its bog habitat
Portrait of the beautiful Arethusa






















Unlike many other species of orchids that can have long-lived individual plants, the dragon's mouth orchid is generally quite short-lived and only lasts a handful of years.  Due to this, the species relies heavily on its seed production from year to year to persist in its bog habitat.  Years with late frosts or freezes can be problematic in that endeavor and potentially set any population back in the coming growing seasons.

Royal Fern (Osmunda regalis) beginning to sporulate 

If the dozens of Arethusa is what brought us to the bog, then the countless other rarities and acidophiles is what kept us around and exploring all morning.  Almost all the plants that occurred out on the sphagnum mat were species I hardly ever get to lay eyes on and spend quality time with in the field.  With so little appropriate and intact habitat left for them in Ohio, combined with the fact what is left is on the complete other end of the state from me makes any visit all the more worthwhile.

Bog Birch (Betula pumila)
Bog Willow (Salix pedicellaris)






















Two of the most common shrubby species growing among the dragon's mouth orchids and lively green sphagnum were the aptly-named bog birch (Betula pumila) and bog willow (Salix pedicellaris).  Both are state-listed species back home at the extreme southern limits of their distributions but much more common just a bit further to the north.

Highbush Blueberry (Vaccinium corymbosum)
Poison Sumac (Toxicodendron vernix)






















Two other frequent shrubs to be found on the bog mat could not be further apart of the spectrum of desirability. On one end you have highbush blueberry (Vaccinium corymbosum) ensconced in maturing, delicious blueberries that upon ripening are impossible to keep your hands (and mouth) off of.  On the other is the dreaded poison sumac (Toxicodendron vernix), one of the last things you would want to put your hands on.  Fortunately, I seem to be able to withstand limited exposure to it and its poison ivy (T. radicans) brethren but you can still never be too careful.

Deciduous needles of the Tamarack (Larix laricina)

Perhaps the most quintessential aspect to any true sphagnum bog, other than the sphagnum, is the presence of tamarack (Larix laricina) trees.  These conifers are unique in the fact they have deciduous needles that are shed each fall as if it were a broad-leaved angiosperm.  The rich, golden yellow color they exhibit is nigh on unbeatable, especially when in large stands.

Bill (back) and Todd (front) admiring the wonders of the bog from the rickety boadwalk

A short, rickety boardwalk takes you out into the margins of the floating vegetation mat but even the short distance it goes is enough to carry you into a completely different world from the surrounding swamp forest. Above Bill admires the layout of the bog while Todd makes camera love to some exquisite patches of the carnivorous round-leaved sundew (Drosera rotundifolia).  Other typical bog associates such as bog buckbean (Menyanthes trifoliata), leatherleaf (Chamaedaphne calyculata), bog rosemary (Andromeda polifolia), small cranberry (Vaccinium oxycoccos), large cranberry (V. macrocarpon), marsh fern (Thylepteris palustris), soft-leaved sedge (Carex disperma) prickly bog sedge (C. atlantica), thin-leaved cottonsedge (Eriophorum viridicarinatum), and some spike rushes (Eleocharis spp.) were present at the site as well.

The numerous branching stems of a bladderwort (Utricularia spp.)

Since bogs are naturally nutrient-poor ecosystems, especially in nitrogen and phosphorous, many plants have to resort to other methods to meet their sustenance needs.  A highly-specialized group of plants known as bladderworts (Utricularia spp.) have met that challenge with a taste for flesh in their carnivorous, bug-eating habits.  The long, lacy strands photographed above are the underwater stems of a bladderwort, where tiny sac-like bladders occur and wait for their next meal to swim by.  Each bladder is set under negative pressure and when one of its tiny sensory hairs is triggered by a passing aquatic organism, a trap door is opened and the prey and surrounding water is sucked inside.  This process from trigger to capture all happens in mere thousandths of a second at a nearly microscopic level!

Mud Sedge (Carex limosa)
Creeping Sedge (Carex chordorrhiza)






















Bogs are not only exciting for the number of unusual orchids they harbor but for the wide variety of sedges they contain too.  The mud sedge (Carex limosa) is a handsome little fellow with its dangling infructescence containing light green perigynia contrasted attractively by its dark brown pistillate scales.  Another typical bog associate was the creeping sedge (C. chordorrhiza), named for its long running stolons that send up a single fruiting culm topped with clusters of brown and straw colored perigynia.  To be completely honest, I could do an entire post dedicated to the sedges and Cyperaceae members of bog habitats but I'll let you all off with just these two instead.

Pink Lady's Slipper (Cypripedium acaule)

The aforementioned Arethusa was far from the only orchid species to occur on the floating vegetation mat as a handful of others could be found in varying stages of bud, flower, and fruit.  The pink lady's slippers (Cypripedium acaule) were still hanging on to their blossoms and color on the raised hummocks under the blueberries and poison sumac.  Seeing them grow on a bog mat is quite the change from their typical habitat of dry, acidic pine/oak woods in Ohio and further south.

Large Whorled Pogonia (Isotria verticillata)
Large Whorled Pogonia (Isotria verticillata)






















Speaking of orchids that one only ever sees growing in dry, acidic woodlands, the presence of large whorled pogonias (Isotria verticillata) growing right out of the sphagnum along the shrubbier bog margins was borderline unbelievable as well.  I've read where in the northern reaches of its range it can occur in this very habitat setting but it was still a shock to witness firsthand.  They were all but done flowering and setting to seed but still a wonderful discovery nonetheless.

Northern Pitcher Plant (Sarracenia purpurea)

Stepping back into the theme of carnivorous plants, I'd be remiss if I didn't make mention of the plethora of northern pitcher plants (Sarracenia purpurea) strewn out across the bog mat in spectacular numbers.  Their modified leaves create the "pitcher" that fills with rainwater and acts as drowning basin for any unlucky insect or fly that finds its way inside.  Upon the pitcher's prey's death, the real work begins as the tiny midge, mosquito, and fly larvae that live within the pitcher's water begin to feast on the drowned carcasses.  Their waste and miniscule leftovers sink to the base of the pitcher where its nutrients are subsequently absorbed.  The pitcher's own secreted digestive enzymes help along with the process as well.

Budding stalks of the rare prairie fringed orchid (Platanthera leucophaea)

I'll close with arguably the most intriguing and surprising denizen of all that calls this particular southeastern Michigan bog home.  In a select area of the vegetation mat grows a handful of the federally threatened and very rare prairie fringed orchid (Platanthera leucophaea).  They were just coming up and starting to bud during our foray into the bog but they were there nonetheless and left my mind utterly blown by their presence.  It's one thing to see the pink lady's slippers and large whorled pogonias on the bog mat as they are well known acid-loving plants but the prairie fringed orchid tends to be a more neutral-basic associate of fens, wet prairies/meadows, and marly shorelines.  It just goes to show how the wonders of a bog are nearly endless and you just never know what you're going to find.  I hope to get back up there in a few weeks to catch these in flower, as despite having sites much closer by it's hard to pass up on the opportunity to see them bloom in such an atypical habitat.

Tune back in soon for part two where we leave the acidic bogs behind in favor for the more sweet and alkaline fens and the spectacular flora within.

3 comments:

  1. An absolutely fascinating post! It all sounds so familiar to the bogs here in southern Ontario. I kept recognizing the plants. Intriguingly, the same species are often found in the fens in the west shore of the Bruce Peninsula, including lots of Arethusa. We think of that habitat as alkaline, but there's often a thin layer of sand on top of the limestone. An interesting botanical puzzle for me that both bogs and fens have these rare species.

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  2. I wonder if we might have visited the same bog. I've been to a couple with Ellen Elliott Weatherbee and Matt Huhmann (sp). You saw more blooming than I did, however. It's all in the timing! PI and I have such a bad history, I am concerned that Poison Sumac might actually kill me, so as much as I love botanizing, I have to be extra careful in bogs.

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  3. Ah, looks like Paradise to me! I missed our Arethusas this year, so what a treat it was to find them on your blog. I believe the Utricularia leaves you show floating in water are those of U. intermedia, which is one of the earliest of the bladderworts to bloom where I live in northern NY.

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