Saturday, October 3, 2009

A rare orchid

Lakeside Daisy State Nature Preserve, Marblehead Peninsula, Ohio. Just a stone's throw from the Lake Erie shore. Looks like a lunar landscape, eh? Not at all, as we shall see; indeed, the place was established as a preserve to protect one of the rarest plants in the U.S., the federally threatened Lakeside Daisy, Tetraneuris herbacea. I made two impromptu field trips here during the recent Midwest Birding Symposium, and we had scads of migrant birds in the surrounding trees. When we weren't looking up we looked down at the dazzling vegetative treats that follow.

Large Milkweed Bugs, Oncopeltus fasciatus, cluster on the pods of a milkweed that is rather rare and local in the state. It is Sand Milkweed, Asclepias hirtella. When in full bloom, the flower clusters resemble bursts of exploding fireworks shooting from the leaf axils.

Elfin in the extreme is the Narrow-leaved Summer Bluets, Stenaria (Houstonia) nigricans, sometimes known by the charismatic name of Diamondflower. Most were long gone, but enough tiny flowers remained to grab our attention. This is a rarity in Ohio, known from only a few scattered sites, but if the spot is favorable, there can be thousands of plants, as here.

Good-looking and conspicuous was Pringle's Aster, Symphyotrichum pringlei. I tend to be more a lumper than splitter by nature in affairs of taxonomy, but not here. Current wisdom has this species reduced to a varietal rank of Ohio's most common aster, the Awl Aster, Symphyotrichum pilosum. Treated that way, our beauty above takes on the cumbersome trinomial of Symphyotrichum pilosum var. pringlei.

Pringle's Aster is very different, though, both in habitat and physiology, and I suspect that one day it'll be carved from the pack and treated distinctly. It's a rarity around here, too, being found on barren limestone pavements such as we are now visiting, and ecologically similar cedar glade prairies in Adams County.

Star of the show, though, was this little plant, its tiny white spires of flowers scarcely visible more than 30 feet away.

Like all Spiranthes orchids - nearly ALL orchids for that matter - the flowers are works of art up close. This is the Great Plains Ladies'-tresses, Spiranthes magnicamporum, which inhabits alkaline prairie barrens. The curved upper sepals resemble the horns of a charging bull. Belly-flopping onto the cold hard rock is required to see this level of detail, but it's time well spent.

It seems as if the flowers are lit from within; a dim golden aura issuing from deep within the throat. Maybe elves live inside, but a more plausible explanation is that the yellowish cast attracts pollinators.

Should you find yourself in this region next May for the avalanche of spring bird migration, try and make time to visit the seemingly barren 19-acre Lakeside Daisy State Nature Preserve. Then, the rocky substrate will be carpeted yellow with the flowers of the Lakeside Daisy, creating one of the absolute must-see natural spectacles anywhere in the Midwest.

1 comment:

Weedpicker Cheryl said...

Great post Jim, almost as good as being there! Thanks too, for the updated nomenclature on the daisy.

It is most amazing how you keep all the names straight!