Asclepias Sullivantii

Asclepias Sullivantii

Various insects visit the flowers of Prairie Milkweed for nectar, including bumblebees, cuckoo bees (Epeolus spp.), leaf-cutting bees (Megachile spp.), Halictid bees (including green metallic bees), Halictid cuckoo bees (Sphecodes spp.), sand wasps (Bembix spp.), Sphecid wasps, Ichneumonid wasps, thick-headed flies (Conopidae), Tachinid flies, flesh flies (Sarcophagidae), butterflies, skippers, moths, and ants (Robertson, 1929). The Ruby-throated Hummingbird also visits the flowers for nectar. Among the various visitors, bumblebees and other long-tongued bees are the most effective in cross-pollinating the flowers. Other insects feed on the roots, stems, leaves, flowers, and seedpods of Prairie Milkweed and other milkweeds (Asclepias spp.). The larvae of one species, the Milkweed Leaf-miner Fly (Liriomyza asclepiadis), tunnels through the leaves of Prairie Milkweed (Betz et al., 1997). Other insects that feed on milkweeds include long-horned beetles (Tetraopes spp.), the Swamp Milkweed Leaf Beetle (Labidomera clivicollis), the Milkweed Stem Weevil (Rhyssomatus lineaticollis), the Small Milkweed Bug (Lygaeus kalmii), the Large Milkweed Bug (Oncopeltus fasciatus), the Oleander Aphid (Aphis nerii) and other aphids, caterpillars of a moth, the Delicate Cycnia (Cycnia tenera), and caterpillars of a butterfly, the Monarch (Danaus plexippus). The Insect Table provides additional information about these species. Because the foliage of Prairie Milkweed contains a white latex that is bitter-tasting and toxic, mammalian herbivores avoid consumption of this plant.

Prairie Milkweed (Asclepias sullivantii) somewhat resembles Common Milkweed (Asclepias syriaca) in appearance, but the former species has flowers that are slightly larger in size and its leaves are hairless on their undersides. Prairie Milkweed is usually a shorter plant than Common Milkweed, and it produces fewer umbels of flowers from the axils of its leaves. Another similar species is Purple Milkweed (Asclepias purpurascens). This latter species differs by having seedpods that are always smooth (rather than bluntly warty) and it has short hairs on the undersides of its leaves. In addition, the flowers of Purple Milkweed are slightly smaller in size than those of Prairie Milkweed, and they are usually more purple. Sometimes Prairie Milkweed has difficulty in forming seedpods because many flower-visiting insects are not very effective in removing and transferring pollinia from one plant to another. In addition, it is not uncommon for some of these insects to become entrapped on the flowers and unable to escape. Another common name of this plant is Sullivant's Milkweed. Sullivant’s Prairie Milkweed (Asclepias sullivantii), is considered one of the best Monarch-attracting plants for the garden. It's large, summer blooming pink flower clusters are rich with nectar and it's well behaved in the garden, spreading slowly by deep rhizomes. The large semi-succulent foliage is attractive and held on sturdy upright stems which make it a handsome standout in the perennial border. A rare Midwestern species, Prairie Milkweed grows well in a variety of soil types including clay where it needs moderately moist conditions and full sun. Recommended companion plants include Purple Coneflower (Echinacea), Obedient Plant (Physostegia) and Big Bluestem Grass (Andropogon). (Source: www.highcountrygardens.com)