Wednesday, November 26, 2008

Lucky Leaf leads to lots of Lichens

In the world of field botany and rare plant seeking, a bit of luck always helps. It's mostly skill - one has to know the common species well in order to recognize the unusual. And the botanist has to be very much aware of habitats and especially the nuances of micro-habitats in order to place himself/herself into situations where rarities might be found.

But a bit of luck always come in handy.

Early last April, a few friends and I went botanizing in Lawrence County, about as far south in Ohio as one can get. You can read more about that mission right here. Rolling along a country lane, I saw a roadside covered with Moss Phlox, Phox subulata. Not one to miss a good photo op with one of our most beautiful native wildflowers, we screeched to a stop and leaped out to snap some photos. What then happened is not uncommon when some good plant hunters converge on a site. Dan Boone, Ray Showman, and Jim Mundy began combing the slope while I tried for the perfect phlox shot.

Soon, one of them - I think it was Dan - stumbled upon a four-leaved clover! Sharp eyes to be sure, as there was plenty of the weedy non-native Red Clover, Trifolium pratense, growing on the roadbank and it is easy to ignore such plants when better finds might be made.

Four-leaved clovers are strongly associated with good luck. Some estimates claim that only one in ten thousand clover plants will produce an extra leaf. There are a number of legends purporting to explain the good luck that comes with four-leaved clovers, and here's a good one: on a normal three-leaved clover, each leaflet has significance. The first represents faith, the second equals hope, and the third means love. Add a fourth leaflet, and you've got a charm for luck.
To be scientifically pragmatic about it, and hopelessly unromantic, the fourth leaflet is merely a genetic anomaly. If you've got enough of anything, a small percentage will express abnormal traits. I've seen Common Boneset, Eupatorium perfoliatum, with leaves whorled in threes - it normally has two leaves. One occasionally stumbles into doubled flowers in the wild, like the rose breeders work hard to produce. And so on.
The reason four-leaved clovers turn up with some frequency is likely just a numbers game: there are millions of clovers plants around, so the odds of abnormality are greater, and so are the odds of someone finding the extra-leaved oddity.

But find one we did, and coincidence or not, the rest of the trip produced some stunning finds.
Ray Showman, Ohio's premier lichen expert, studying a lichen-encrusted tree trunk in remote Lawrence County not long after the four-leaved clover find. We went to this spot seeking a rare plant that I knew to be present, and ended up stumbling into an absolute treasure trove of lichen diversity.

Ray quickly found this state-endangered lichen, known but from only one or two Ohio locales prior to this find. It is Ramalina farinacea. Sexy name, huh? So far, the lichenologists have not managed to come up with alluring common names for many species, but I wish they would. I've seen two common names for this one. Dotted Ramalina is one. OK on the dotted part, but most people would say "what the heck is a Ramalina?" The other is far worse: Farinose Cartilage Lichen. Blech!

Whatever you call it, the lichen is a charmer, quite beautiful upon close inspection.

This was the BIG FIND, though, and the one that just maybe that odd clover led us to. It is Usnea substerilis, which is a first state record. This was very cool to stumble upon. It looks like a rotund piece of Spanish Moss springing from the side of the tree - very distinctive. I don't think anyone has even bothered to give this one a common name, although Usnea lichens in general are called beard lichens.
Who cares? I mean, what good are these mossy green tree crusts, anyway?
Ray Showman was the first, and maybe the only, biologist hired by a power company to study lichens. In Ray's case, American Electric Power gave him a job. Lichens are conspicuous and extremely sensitive air quality indicators. Their presence - or absence - reveals much about the health of the air and what contaminants are or aren't present. When Ray first began studying lichens near some coal-fired plants, no lichens could be found for huge swaths around the plants. As scrubber technology advanced and emissions became cleaner, lichens returned.
Hummingbirds and gnatcatchers also like lichens. They shingle the exteriors of their nest with lichens bound by spiderwebs. The elasticity of this construction allows the nest cup to expand as the young birds grow, and the lichens blend the nest with the bark.
Yellow-throated Warblers are bark-creepers, and often spend foraging time nosing in lichen clusters seeking the numerous insects that seek refuge there. One fascinating insect group co-evolved with lichens are some of the lacewings. Their larvae bedeck themselves with lichen bits essentially glued to their backs. Impossible to see, until a chunk of the lichen gets up and walks off.
Lichens look fantastic in winter, and that's a great time to look for them. Ray and I are heading back to this part of Lawrence County in early December, and it'll be interesting to see what turns up. Probably won't have any four-leaved clovers to give us extra luck, though.

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