Foamflower (Tiarella cordifolia)
Somewhat uncommon here, but found on some wooded hillsides; these plants grew near the Trillium Trail in Fox Chapel. They bloom around the first of May, just when the trilliums and Virginia Bluebells are at their peak.
From Gray’s Manual:
TIARELLA L. FALSE MITERWORT
Calyx bell-shaped, 5-parted. Petals 5, with claws. Stamens long and slender. Styles 2. Capsule membranaceous, 2-valved; the valves unequal. Seeds few, at the base of each parietal placenta, globular, smooth. Perennials ; flowers white. (Name a diminutive from tiara, a tiara, or turban, from the form of the pistil, which is like that of Mitella, to which the name of Miterwort properly belongs.)
1. T. cordifolia L. Leaves from the rootstock or summer runners, heart-shaped, sharply lobed and toothed, sparsely hairy above, downy beneath; stem (1-4 dm. high) leafless or rarely with 1 or 2 leaves ; raceme simple ; petals oblong, often subserrate. Rich rocky woods, N. S. and N. B. to Minn., Ind., and southw. in the mts. Apr.-June.