Sun/shade: Full sun to part shade
Soil moisture: Medium
Flowering period: August
Host plant for 16 caterpillar species
With its single stem branching outward to form a broad, circular flower cluster, the shape of this whimsical wildflower has been likened to a small umbrella or parasol. Growing best in soils of moderately wet to average moisture and under full to partial sunlight, flat-topped aster is native to NE Ohio wet meadows, openings in wet woods, and woodland margins. One great place to view flat-topped aster in the Cleveland area is along the trails near Lake Isaac and Beyer’s Pond in Big Creek Reservation. Blooming for a period of 1-2 months in late summer and fall, the plant’s numerous flowerheads are a late season source of floral rewards for pollinators, including several species of specialist bees.
In 2020 it was documented that a native species of sawfly, Macrophya flavolineata, utilizes flat-topped aster as its larval host, feeding on the plant’s foliage. Just as moth and butterfly caterpillars are a critical food source for birds, sawfly larvae are as well, providing especially valuable nourishment to nestlings. The fact that larvae have been identified for just 25% of the approximately 1100 North American sawfly species and that the host role of plants like flat-topped aster is still being discovered suggests that native plants are even more important to supporting food webs than is presently known.
Photo by Ashley Keesling.