Spreading dogbane

Prepared by Jennifer L. D’Appollonio, Assistant Scientist, University of Maine, Orono, ME 04469. Updated February 2018.

Scientific name: Apocynum androsaemifolium L.

Common name(s): spreading dogbane, fly-trap dogbane, bitterroot

Links: USDA PLANTS Profile , NPIN Profile, Go Botany

Images: (to see enlargements [PC]: click on image, then right click and choose “view image”)



-wide spread branching red stems

-can reach up to 2 feet tall

-leaves are opposite

-bell shaped flowers

spreads through patches of rhizomes

-contains a milky white sap that is toxic to humans

-generally flowers June through August in ME

Reddish stems 1′-4′ tall grow from horizontal rootstocks, branches smooth and spreading.  Oval leaves opposite, 2″-4″ long and 1″-2.5″ wide, often drooping on short stalks.  Flowers pinkish, bell-shaped and about 1/4″ wide, seed pods 4″ long and narrow, can be confused with bush honeysuckle.  All parts exude white liquid when broken.

-may be confused with A. cannabinum; see left sidebar on Go Botany webpage


-disturbed areas

-road sides

-waste areas


-produces nectar as an important food source

-attracts monarch butterflies

Natural History:

-native to North America

-genus “Apocynum” means “away from dog”

-its tough fibers were used to make threads and cords by Native Americans

-the root contains cymarin, a cardiac stimulant



Hansen, R.W., S.B. Hansen and E.A. Osgood. 1991. Reproductive phenologies of selected flowering plants in eastern Maine forests. ME Agric. Exp. Station Tech. Bull. 143. 17 pp.

Heinrich, B. 1976. Flowering phenologies: Bog, woodland, and disturbed habitats. Ecology. 57(5):890-899.

Greenlee, Jack. “Spreading Dogbane (Apocynum Androsaemifolium).” Plant of the Week, U.S. Forest Service, www.fs.fed.us/wildflowers/plant-of-the-week/apocynum_androsaemifolium.shtml.