Monday, August 31, 2009

Stars Blazing! Liatris scariosa var. nieuwlandii and Liatris aspera


Starting about mid-May, every time I visit a prairie remnant I think, "This is the most beautiful time of the year on the prairie!" Then, I visit a week or two later and think, "No, this is the most beautiful time..." Such was the case yesterday at Cressmoor Prairie in Lake County, Indiana. There were Sunflowers of many kinds, Silphiums in abundance, Goldenrods in profusion, Blazing Stars a plenty, and tall, tall grasses in anthesis! And the varied, colorful, and busy insect life...wow!
Savanna Blazing Star (Liatris scariosa var. nieuwlandii)
Cressmoor is one of just a few places in northern Indiana where it's easy to see Savanna Blazing Star (Liatris scariosa var. nieuwlandii). It differs from Rough Blazing Star (Liatris aspera) in having middle involucral bracts non-bullate (not puckered, swollen, or blistered) and flowering peduncles as long as- or longer than the involucres. And, while rarely mentioned in manuals, its upper stems and peduncles are often infused with a dark maroon or purple color.

Savanna Blazing Star (Liatris scariosa var. nieuwlandii)

Rough Blazing Star (Liatris aspera). Note the bullate (puckered, swollen) involucral bracts. Photographed in dry sand prairie along the edge of the Liverpool Sandpits in Lake County, Indiana.

4 comments:

Scott said...

Keith,

Your photos never cease to amaze. Great work!

To distinguish between L. aspera and L. scariosa v. nieuwlandii, I would add that L. aspera typically has narrower basal leaves (linear to lanceolate, 1-2 cm broad) than L. scariosa v. nieuwlandii (lanceolate to narrowly ovate or obovate, 2-5 cm broad).

Scott.

Keith said...

Thanks Scott! For anyone who hasn't experienced Scott's amazing knowledge of vegetative characters, would you believe that he correctly identifies asters and goldenrods (and everything else) in the spring, not long after they emerge from the ground? It's true, and I'm not kidding or exaggerating! He will attempt to deny it, but don't listen!

James C. Trager said...

I'm very fond of this genus, Justin, and especially of L. scariosa. Thanks for posting this.

I suspect the reason the deep maroon color doesn't get mentioned much has to do with reliance on herbarium specimens, where it is less evident. Further, many L. aspera suddenly acquire a good bit of purple color once they reach anthesis.

Scott said...

Well, re: Keith's comment, I would deny it, but since he has instructed you not to listen, I will agree that I can identify some asters and goldenrods and other things vegetatively. There, I said it. But I've learned the majority of those vegetative characters from Justin and Keith, so I can't really take the credit.