Asclepias subverticillata

Asclepias subverticillata, also known as whorled milkweed, is a species of milkweed native to North America. It is a perennial herb that is known for its distinctive whorled leaves and small, white flowers.

Description

Asclepias subverticillata grows to a height of 1-3 feet and has a spread of about 1 foot. The leaves are narrow and linear, arranged in whorls of 3-6 around the stem. The flowers are small, white, and borne in clusters at the top of the stem. The fruit is a slender, erect pod that contains numerous brown, flat seeds.

Distribution and habitat

Asclepias subverticillata is found throughout the western and central United States and into northern Mexico. It is most commonly found in dry, open areas such as prairies, fields, and roadsides. It prefers well-drained soils and full sun.

Ecology

Like all milkweeds, Asclepias subverticillata is a host plant for the monarch butterfly. The caterpillars feed exclusively on the leaves of milkweeds, and the toxic compounds in the plant make them unpalatable to predators. The flowers are also an important source of nectar for bees and other pollinators.

Uses

Historically, Native American tribes used Asclepias subverticillata for a variety of medicinal purposes. The plant was also used for making fiber and cordage.

Conservation status

Asclepias subverticillata is not currently considered threatened or endangered. However, like all milkweeds, it is vulnerable to habitat loss due to development and agriculture.

References

• Flora of North America
• USDA Plants Database