Saturday, August 11, 2012

Rare plant found at Meadowbrook Marsh

A relatively "new" place that is getting much attention these days is Meadowbrook Marsh, on the Marblehead Peninsula in Ottawa County. It's not new, of course - I remember stopping regularly to scope out its wetlands many years ago, when driving along the south side of the massive limestone archipelago. But what IS new is that the forward thinking Danbury Township trustees have secured much of the land that comprises the Meadowbrook wetlands, and made it accessible to people in a way that it never was before.

Meadowbrook Marsh really got on the birding community's radar screen during last year's Midwest Birding Symposium at nearby Lakeside. Thanks in large measure to the efforts of Cheryl Harner, MBS raised funds for Meadowbrook and the site was one of our primary MBS birding sites. Meadowbrook is now much better known among the binocular-toting set than it was pre-September 2011. Through a creative carbon offset program sponsored by the Ohio Ornithological Society at MBS, and bolstered by an OOS match, over $7,000.00 was raised to purchase more Meadowbrook property.

The approximate boundaries of Meadowbrook Marsh, outlined in red. Not all of the circled area is yet protected, but the Black Swamp Conservancy is working on an additional purchase, which will be helped by the aforementioned OOS funds. Support your local land trusts, and ornithological societies!

So, the other day found me leisurely tooling eastward along East Bayshore Road, which heads right by Meadowbrook Marsh. I was on my to the Kelleys Island Ferry and eventually that massive island out in Lake Erie, but I slowed my pace as I passed the marsh. As usual, a bunch of herons were standing around amongst the American lotus, and I thought that I'd better make a quick stop and scope them out. Lots of Little Blue Herons around of late, you know.

Anyway, I'm standing under the shade of the remnants of a tattered ash borer chewed green ash tree, scanning the scene above. First focusing on distant objects - the herons - I finally glanced down, and whoa! I noticed that lush bed of greenery in the lower right corner of the photo.

A luxuriant patch of deer's-tongue arrowhead, Sagittaria rigida! This beautiful little wetland plant is a bonafide rarity these days, and colonies are few and far between in the Lake Erie marshes. It was added to Ohio's rare plant list about 20 years ago, and is currently listed as potentially threatened, which is a watch-list category.

In pre-colonial days, prior to the massive manmade changes to Lake Erie's shoreline and the attendant destruction of many of the buffering wetlands, deer's-tongue arrowhead was far more common. Enter the more recent problems wrought by invasive plants such as common reed, Phragmites australis, purple loosestrife, Lythrum salicara, and flowering-rush, Butomus umbellatus, and native marsh plants such as this have suffered even more. This arrowhead is rather finicky; it likes to occupy autumnally exposed mudflats - a habitat that is subject to being quickly overrun by botanical nasties such as the flowering-rush.

If you've spent much time slogging in or around wetlands, you've probably seen arrowheads. The most common is the rather robust common arrowhead, Sagittaria latifolia. It has big broad leaves with arrow-shaped lobes at the base, and like the other arrowheads, bright white three-petaled flowers. Probably 99% of the arrowheads one encounters around here will be that species.

But there are seven other Sagittaria species known from Ohio, and in addition to the deer's-tongue arrowhead, a couple of great rarities occur around Lake Erie. Only three of them have the unlobed leaves of deer's-tongue, and close inspection is always warranted to ensure which species one has found. The weird leaves of deer's-tongue arrowhead are little more than flattened and widened upper portions of the leaf's petiole. One must take care when judging an arrowhead by its leaves, however. They can be quite variable, depending upon the environmental factors that the plant is exposed to.

The other portion of the plant in the upper part of this photo is the scape, or flowering stem. Its characters are consistent and more important than leaves are for identification. The little balls are the fruit heads, and note how the scape bends sharply at the lowest (largest) fruiting head. That's a good identification character; probably diagnostic for Sagittaria rigida.

If one dissects a mature fruiting head, this is the result - lots of little seeds, or more technically achenes. The shape of each species of arrowhead's achenes is unique. The actual seed is surrounded by a thin papery waferlike structure - ideal for floating the seed to new locales. The seed within is capable of longterm "seedbanking"; surviving extended periods buried in mud. Seedbanking is a common survival strategy for plants that live in ephemeral habitats, such as deer's-tongue arrowhead. Years may pass before its favored mudflats reappear, but when they do the plants will magically reappear, even if they've not been seen for decades.

We can never protect too many wetlands, especially in the biologically rich hotspot region of the western Lake Erie shoreline and adjacent Sandusky Bay. Kudos to Danbury Township for working hard to conserve Meadowbrook Marsh, and to the Black Swamp Conservancy and the Ohio Ornithological Society for their important roles in protecting this state treasure.

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