Thursday, May 21, 2009

A few rare "weeds"

I had a couple of great botanical expeditions to southern Ohio back in April, and the following are some shots for the botanically inclined readers of this blog. Of course, we should ALL be of a botanical bent; the birds and other animals that we enjoy depend upon vegetable matter.

A tip of the vasculum is in order to the one and only Daniel Boone, who put me onto these populations.

A weedy roadbank along U.S. 52 in Adams County, skirting the north bank of the Ohio River and a mere stone's toss from the old hills of Kentucky. Not a habitat to stir the soul, at least at a casual 60 mph glance from the sedan.

But the sharp-eyed plant seeker might screech to a halt after spotting these tiny gleams of snow-white jutting from the Kentucky Fescue. And this is no weed, like its roadbank fellows. It is the rarest of Ohio onions, a plant known as False Garlic, Nothoscordum bivalve. Listed as endangered in our state, it occurs in an extremely limited area of Adams County, with one curious population far removed in Clark County.

Some onions, such as the Field Garlic, Allium vineale, or Wild Onion, A. canadense, common in fields, lawns, and the latter floodplains, rarely flower. They typically reproduce via vivipary, or the production of bulblets in place of flowers. Not so with this stunner - the flowers are every bit the match of much larger, more conspicuous lilies.
While rare here, that's just because Ohio is at the extreme northern limit of the range of False Garlic. I once drove to Texas in early spring, and this plant become an increasingly abundant sight along the roadsides as I moved south.

An even weedier habitat than the above, if possible, and not far away. This rutted dirt lane bisecting fields variously planted in beans or corn harbored a most interesting buttercup, and one that very few people have seen in Ohio. Hardly a native species to be found, and the dominant blooming biomass - that huge purple splotch left of the road - was an alien mint, Purple Dead-nettle, Lamium purpureum.

But this bizarrity was what we had come to see. And we were among the very few who would take two strides out of their way to see it, I suspect. From an upright position, this elfin buttercup looks all the world like some sort of grass. But it's not, and I bet a botanist stumbling upon Mousetail, Myosurus minimus, for the first time will do some serious headscratching and floundering through the botanical keys.

A closer look at the blooming inflorescence. Those whitish appendages at the base of the flower spikes are the sepals; the tiny flowers form the aggregate spike. A definite oddity, but it has a bit of a charm to it when closely admired.
And controversy embroils this herb. Is it native, or is it not? If it is, Mousetail should probably be listed as endangered or threatened, as only three or so populations are known in the state. All of them are in the rich alluvial soils of floodplains. But just because it looks weedy and acts weedy doesn't mean it is a non-native invader. My hunch is that Mousetail is an indigenous part of the Ohio flora; a riverine migrant dispersing itself along floodplains, aided by floodwaters. Such plants, historically, would have been far scarcer and confined to naturally occurring scour barrens resulting from severe flood events. Modern agricultural practices have incidentally created similar conditions, and on a much bigger scale, and this bite-sized buttercup has taken advantage.

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