Monday, April 30, 2012

Plant Quiz Solved: Seaside Arrow-grass (Triglochin maritima)

Congrats and thanks to Justin for correctly identifying this plant as Seaside Arrow-grass (Triglochin maritima).  This unusual and rare species is listed as threatened in Ohio largely due to its ever-shrinking habitat of calcareous fens, marshes, swales and sandy beaches.  It's very similar to another species; Marsh Arrow-grass (T. palustris) which is also rare in Ohio, where they can occasionally grow alongside one another.  Seaside arrow-grass is much larger and more robust containing flowers on shorter, nearly sessile peduncles and six stamens/carpels; while marsh arrow-grass is smaller, thinner and has three stigma/carpels on flowers with longer peduncles. 

*Update*  Some additional clues to the identity of this species is its circumboreal distribution; the fact it is a monocotyledon; and the blurred background contains a diverse display of last year's grasses, sedges, spikerushes and bulrush in a wet, alkaline habitat.

Here is this week's plant quiz.  Take a look at the photograph below and comment with your answer or best guess!  Both plants in the picture are the same thing with the left specimen in full bloom.  Notice the blurred background hinting its typical habitat here in Ohio.  Good luck!


8 comments:

  1. This one I have never seen. I await your ending my suspense.

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  2. If you only knew how long I spent on this one. Then I read "in full bloom". That threw my list out the window. Guess I'll sit back in frustration and call it an orchid-equisetum-ragweed hybrid. Ya, that's the ticket.

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  3. i still think it looks like an early blooming Chamaelirium

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  4. It's not Chamaelirium but it is a monocot. Another hint is it has a circumboreal distribution and the blurred background consists of last year's dead stems of sedges, spike rushes and grasses...

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  5. How about Triglochin palustris? I know T. maritima is also in Ohio but I've never seen it and it is difficult to see determine what the fruits will look like through those sepals.

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  6. Excellent job, Justin! I'll go ahead and count it correct since you mentioned T. maritima.

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  7. Thanks for taking pity on me, Andrew! And thanks for the info on how they differ. I suspected the T. palustris had stalked flowers and a less dense inflorescence but wasn't sure. They are both handsome plants.

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  8. They are handsome! I love our fen complexes here in west-central Ohio and can't seem to get enough of the unique and fascinating flora within. I figured this species may throw people for a loop but knew in the end someone (especially like yourself) would chime in with the right answer.

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