Asclepias meadii


Asclepias meadii, (Mead’s milkweed)

General Description

The U.S. Fish & Wildlife Service officially listed A. meadii as “Threatened” in 1988. Though historical records indicate this species has always been rare (Woodson, 1941) due to the loss of native prairies by agriculture and urbanization.

Many areas in which Mead’s milkweed grows are often unsuitable areas for plowing and have been used instead as hay meadows. The perennial nature of Mead’s milkweed has allowed it to survive annual mowings for generations. Unfortunately, most hay meadows are mowed before the seeds mature and as a consequence, A. meadii may experience a decline in genetic variation. This species has proven difficult to propagate. Studies suggest that periodic prescribed burnings between September and April stimulate sexual reproduction in Mead’s milkweed, and could be significant in conserving this species.


Form/Growth

Distribution: IA (Endangered), IL (Endangered), IN (Reintroduced), KS, MO (Endangered), WI

Flower: Usually has one nodding umbel per stem, approximately 15 flowers with .8 inches long pedicels (stem that attaches the flower to the main stem or known as inflorescence). Flower color is greenish or slightly yellow with occasional hints of purple, and the texture of the flower appears to be waxy. The individual flowers have 5 tubular hood shaped structures; and have horns that protrude out from them.

Foliage: Hairless. Single narrow thin stem. Has a pale grey or bluish green color (glaucous). Herbaceous (the plants leaves and stems die at the end of the growing season)

Growth Period: Spring

Habitat: Native tall grass prairies and some glades in the Ozarks, Missouri. It grows well in prairies that are regularly burned and in rocky open areas. In general areas with low competition from other plants.

Height: 12-24-36 in.

Leaves: 2- 6 pairs of opposite, narrow, tapering off to a point. Length 2-2.8 inches. Width .4-2 inches. Hairless.

Toxicity: Unknown


Reproductive

Blossoming Season: May to June

Life span: A single stem will produce flowers for 2-3 years then will terminate or go dormant.

Propagation: By seed.

Pods: Seeds mature from July to October. Color of the pods are originally green, but as they mature turn brown. Pods grow to be 1 ½ to 4 inches long.


Environment and Growth Requirements

Maintenance: Low.

Overhead Conditions: Not shade tolerant. Needs to be out in the open with plenty of sunlight.

Precipitation: 20-60 in (51-152 cm) annually.

Soil Texture: Nutrient rich soils (lots of biomass).

Temperature: Grows in areas with a minimum temperature of -10 to -20 Fahrenheit (-23 to -29 Celcius).


Work Cited: mdc.mo.gov, Plants.usda.gov, MonarchWatch.org, Arborday.org, Eduplace.com

Photos: Monarch Watch Archive