Western Whorled Milkweed

[Asclepias subverticillata (Gray) Vail]

Apocynaceae (Dogbane Family) (formerly in Asclepiadaceae, the Milkweed Family)

▲ ▼ mature plants with flowers

▼ mature plants with flowers

▲ flowering stem showing the side branching common to the species (differs from less-branched whorled milkweed)

▲ ▼ flowers

Asclepias subverticillata (Gray) Vail, Western Whorled Milkweed: (Bayer Code: ASCSU; US Code ASSU2)

A creeping perennial with rhizomes, appearing similar to whorled milkweed
Differs from whorled milkweed in that the stems tend to have more branching in the upper portions on western whorled milkweed
Leaves are linear, in whorls around the stem at nodes
Flowers are greenish-white, in rounded clusters arising from leaf axils near tips of stems
Fruit is a slender pod
Sap is one of the more poisonous of milkweeds, and poisoning is more common with this species
Found in pastures, roadsides, reduced-tillage fields, in good, sandy or clay soils; tolerates wetter soils
More common in western Midwest; not in Missouri

(Updated January 19, 2019)