Also known as Stringy Stonecrop or Wild Stonecrop (a name it shares with Sedum ternatum), this little succulent really likes city yards where the soil is a bit dry. But it can seed itself anywhere and grows very fast: this plant grew up in a nursery pot with a Korean lilac, and by the end of May was covered with starry yellow flowers. Often planted as a groundcover; it can be invasive, but its shallow roots make it very easy to yank out if you don’t like it.
This species was introduced from Asia after Gray’s time as a rock-garden specialty, but apparently Pittsburgh is very much to its liking. It does not appear in Gray’s Manual.
An attractive native Sedum that likes rocky hillsides in open woods. This one grew on a small stone outcropping on a wooded hillside in Mount Lebanon, where it was blooming in the middle of May.
Gray describes the genus and the species:
SEDUM [Tourn.] L. STONECROP. ORPINE
Calyx-lobes and petals 4-5. Stamens 8-10. Follicles many-seeded; a little scale at the base of each. Chiefly perennial smooth and thick-leaved herbs, with cymose or one-sided inflorescence. Petals almost always narrow and acute or pointed. (Name from sedere, to sit, alluding to the manner in which these plants fix themselves upon rocks and walls .)
S. ternatum Michx. Stems spreading, 7-15 cm. high ; leaves flat, the lower whorled in threes, wedge-obovate, the upper scattered, oblong; cyme 3-spiked, leafy; petals white. Rocky woods, Ct. to Ga., w. to Mich., Ind., and Tenn. May.