flat-topped white aster

Doellingeria umbellata (flat-topped white aster). You may be more familiar with this Asteraceae as its older botanical name, Aster umbellatus. The flat-topped white aster is native to wet sand prairies, damp thickets, and wet meadows throughout eastern North America, including Illinois. Doellingeria umbellata grows up to 1.5 m (5 ft.) tall, performing best in full- or partial-sun in wet or damp soils. Plants have a strongly upright habit, producing tall unbranched stems covered in alternate, lanceolate-elliptic dark green leaves.

Flat-topped white aster produces flowers in a flat-headed panicle consisting of white ray florets and yellow disk florets. The later transition to cream-colored after pollination. Flowering occurs July/August to September. During flowering, numerous types of pollinators are attracted to D. umbellata flowers: long- and short-tongued bees, wasps, beetles, flies, and butterflies. The foliage of flat-topped white aster often plays host to caterpillars of the rare Chosyne harrisii (Harris’ checkerspot).