Tuesday, April 13, 2010

Elf Orpine at Forty Acre Rock

Diamorpha smallii
a.k.a. Sedum smallii, Diamorpha cymosa and Sedum cymosa

My husband and I were at Forty Acre Rock Heritage Preserve near Lancaster, South Carolina on the day before Easter.  We had barely made it into the preserve when, in proper plant geek fashion, I rushed over to this tiny red plant and went nuts, "Look honey!  Diamorpha smallii! - and it's blooming, too!"  Actually, it was more like, "Oh my God!  What IS that?  It's red!"  Either way, I was absurdly excited to see such a thing and it remains a highlight of the month for me. 

Elf orpine

I found out later the plant is elf orpine, Diamorpha smallii, and it grows only in outcrops where it fills shallow depressions in the granite making succulent red cushions on the wide expanse of rock. Let me ask you, how in the world can anything grow in a place like that? Do you know how hot a rock gets in South Carolina in the summertime? I'll tell you, fry-an-egg-on-it hot.  Meanwhile the surrounding forest is twenty or thirty degrees cooler! Combine that with a 90% runoff rate when it rains, and you get a really harsh environment with some rare and interesting plants.

I did find out after some investigation that elf orpine is a winter annual. Seeds form by May which then go dormant until late fall when they begin to germinate in the cooler, wetter weather.  Those seeds must be nearly indestructible, but at least the plants don't have to tolerate the Death Valley-esque conditions all summer.
Elf orpine mixed with sandwort.
Did you think this picture is flowering elf orpine?  I did, but it's a reminder to look for leaves and stems attached to the flowers if you're trying to identify something.  Those flowers are sandwort, Arenaria uniflora.  You can see elf orpine flowers in the first photo.

Sandwort by itself. 

Wiry stems and dichotomous branching?  That's Caryophyllaceae, the carnation family.  I love seeing cousins of plants I know and finding the family resemblance!  Doesn't the flower look like oxalis? But no, different family altogether.

Sedum pusillum? I'm not sure, but I do love the bright red pollen! 

Mosses and lichens were abundant at Forty Acre Rock.

Top of the 14 acre rock.

I hope you'll go to a granite outcrop and look for elf orpine and all the other rare and/or endangered plants there.  It's a fascinating trip for plant lovers - I know you'll enjoy it.  But do it now before it gets too hot!

More photos of Diamorpha smallii
Good article describing granite outcrops
Plant Life on Granite Outcrops

Updated:  December 2, 2011


  1. What a fun and interesting little plant. I was hoping Forty Acre Rock State Park would be closer to me... :-( it isn't. Still a doable drive, just longer.

  2. Forty Acre Rock sounds like an interesting place! And the elf orpine IS adorable! Are you going to try to grow it?

  3. i would love to grow it ruth! since wild collecting is out, i'm not sure where i would get some. hmm. i'll look into it.

    janet, it's worth at least a couple hours drive in the spring or fall. i'll bet you would love it.

  4. Thanks for the interesting post. I lived in Charleston for several years and did make it to the Upcountry on occasion, but never saw this.

  5. les, thanks for your comment. i was really surprised by 40 acre rock but what a nice surprise. i bet most people are more familiar with lowcountry sc than upstate. both are pretty, though.

  6. I've just found your post on the Elf Orpine and Sandwort at Forty Acre Rock State Park.
    I've just visited Arabia Mountain Nature Preserve near Atlanta. These sites seem to be very similar.
    Hope I can make it up to 'your' park some Spring.