Asclepias speciosa

Common name:

Showy milkweed

Family:

Milkweed

Region:

U.S.

Habitat:

Waste places, ditch banks, streamsides

Toxic season:

Year-round

Features:

Erect grayish-green plant up to 5' tall containing milky juice. Leaves are opposite, oval, toothless, leathery, hairy, up to 5" long with prominent midrib. Flowers are pink or light purple, 5-petaled with petals extending outward and arranged in showy, umbrella-like clusters at the ends of plant stems. Seeds are hairy and tufted in pod-like fruits.

Poison type:

Cardiac glycosides

Signs/effects:

Staggering, depression, weakness, collapse, dilated pupils, elevated temperature, intestinal irritation, rapid heart rate, labored breathing, coma, death. Signs may occur up to 2 days after ingestion of toxic/lethal amount.

Treatment:

Treatment most effective if begun early. Activated charcoal, electrolytes, purgatives may reduce absorption and promote excretion (gastrotomy/rumenotomy early after ingestion may also be effective). Keep animal calm.

Comments:

All parts toxic, fresh or dry. Unpalatable, but may become more palatable when dry and mixed in hay. Toxic and lethal amounts may be nearly identical at <0.05-2.0% of body weight. Cases of poisoning of all livestock except llamas and alpacas have been reported; the latter two species also may be susceptible.

Next plant
Return to plant list
Return home