Identification Helps:When in flower in July and August, Sullivant's milkweed looks much like the common milkweed, Asclepias syriaca, a frequent species in both prairie and non-prairie areas in Ohio. But Sullivant's milkweed is best distinguished it's more erect leaves and the pink, embedded central vein running down the middle of the leaves.
Late in the season, when seed pods form, they are smooth, even waxy. Common milkweed has rough-surfaced seed pods.
Naturally occurring Sullivant's milkweed is virtually never encountered except in areas that were once native prairie.
Similar Species:Common milkweed is very similar, but has more horizontal leaves that can be somewhat hairy. Common milkweed seed pods are rough. Sullivant's seed pods are smooth and sometimes waxy.
Preferred Growing Conditions in the Wild: Sullivant's milkweed typically grows in native tallgrass prairies on mesic (normal moisture) or slight hydric (wet) sites.
Seasons of Growth and Bloom:The species blooms from late June through July and sometimes into August.
Natural Distribution in Ohio:Sullivant's milkweed was found in all Ohio tallgrass prairies, except in sandy soils.
Description and General Information: This rare prairie milkweed was first technically collected in the Darby Plains prairies west of Columbus. It was named for 19th century Columbus bryologist (moss expert) William Sterling Sullivant. Although closely related to the common milkweed, Sullivant's milkweed grows naturally only on original prairies. When planted from seeds, it can be grown in prairie restorations or reconstructions. It is a high quality prairie indicator.