Thursday, April 15, 2010

Random plant event: Equisetum strobilus

Saw this out on a walk with Sheba, and took a picture because it was weird. My first thought was that it was some sort of mushroom, but something about the little node (almost at the bottom of the photo), which I've never seen on a mushroom before, made me keep looking.

Long story short, it's a horsetail (Equisetum) of some kind; this is the strobilus, a structure which, if Wikipedia is correct and I'm reading it correctly, produces spores. That's about as far as I can get into it before the vocabulary starts being a problem. (I'm writing this in kind of a hurry; I'd try to untangle the vocabulary if I had more time.) Strobili are commonly called "cones," but now that I've told you that, try to forget it, because that's a botanically incorrect term. (Botanists try to save the word "cones" for conifers, though, confusingly, the cones of conifers are called strobili. All cones are strobili, but not every strobilus is a cone. Or something like that.)

Equisetum is the last surviving genus in the class Equisetopsida, which dates back to the Devonian, the era in which Devo's first albums were recorded. (Actually the Devonian goes from 416 to 359.2 million years ago, and rocks of this time period were first studied in Devon, England. Hence the name.) You may have met some ancient Equisetopsida specimens as coal; they used to be the dominant type of understory plant in forests and swamps. Species of Equisetum are currently found everywhere on Earth except Australasia (Australia, New Zealand, and the smallish islands to the north and east of them, but not as far northwest as Indonesia) and Antarctica.

This particular plant is most likely (but by no means certainly) Equisetum arvense, field horsetail, which is distinguished by, among other things, having a truly absurd number of chromosomes (108 pairs). I hear this is a record.

Among the other trivia bits about horsetails in general, and the field horsetail specifically:

The stems are coated with abrasive silica particles, which in the past has made them useful for cleaning metal. (Possibly Equisetum arvense should go on the zombie apocalypse list; dunno whether they can be grown as houseplants, though.)

They're also pesticide-resistant, and can concentrate gold from the soil. Not economically useful amounts of gold, but still.


Don said...

I've seen giant Equisetum used as lobby plants on the west coast---they're big and sufficiently unfamiliar and weird-looking to work well in contemporary interior plantscaping. There they always seem to be planted as a monoculture in big containers. They're also commonly sold for water gardening, and are traditionally used in Japanese gardening in single clumps as a vertical accent. And I've seen a miniature (around three inches tall) sold as a fine-textured grass-like groundcover.

It's always recommended that they be planted in a sunken container. Personally, I'd NEVER introduce them to the garden, as they're tremendously invasive, and I can't imagine they won't escape through any drainage hole. And once they get a foothold, they're impossible to get rid of. You can't dig the runners out, and they're highly herbicide resistant.

Anonymous said...

Yes. they are interesting short-term houseplants. When I was a child, my father split hunks of soft coal to feed our furnace and he'd call me when he found a really great plant impression - that was my first horsetail, but later we used them to scrub our sooty pots when we'd cooked over a campfire. The world of dinosaurs in your own backyard.

Ivynettle said...

I've been seeing a lot of the things too - they're all over the railway embankment. I never noticed them before, though I knew they had to be horsetails because we learned about them in school.

Lance said...

I've always loved them because they are weird, and because of their history. They don't grow around where I live, but I see them thickly in New Mexico. I don't think they like our dry climate here.

Coelus said...

I've seen one or two kinds of Equisetum growing along stream bottoms here in Colorado. They always catch my eye... they're sorta like horseshoe crabs, they just look... old.

I've never tried using them for cleaning, but I've read they're good for eating. I wouldn't eat a ton of them, as they've been known to poison livestock, but in small quantities the young shoots and pulp are edible raw or cooked and supposedly reminiscent of asparagus (of course, always avoid eating specimens growing in unknown gardens since they may have been sprayed with chemicals).

Megan said...

Today we split up an Equisetum hyemale we rescued from the curb several months ago. Way too invasive to put in the ground, but I think it's cool in containers. Wish they didn't love water so much.

Tom said...

Equisetum make me so happy.

Ryan said...

I agree that it it Equisetum arvense: dimorphic stems with yellow short-lived fertile stems in the early spring. That species is also right for your area. You've got a good eye: the strobili are quite short and dirt-colored.

2N=216, while high among plants and utterly surpassing the mammals, is outmatched by the "grape ferns." Try Ophioglossum reticulatum, with a diploid number over a thousand. E.g. Many of its close relatives, such as Botrychium, have more reasonable numbers under a hundred.