Common Milkweed vs Poke Milkweed
These two tall milkweeds are usually easy to tell apart, but they can hybridize, and hybrids have intermediate characteristics between the two. Athough the two species overlap in range, their habitats overlap little, with common milkweed found in sunnier, more open habitats, whereas poke milkeweed is found in shadier habitats sheltered from wind.
Common Milkweed (Asclepias syriaca) | Poke Milkweed (Asclepias exaltata) |
A sun-loving rhizomatous perennial native to a wide range in North America, best known for being a preferred host of the Monarch butterfly. | A perennial plant named for its superficial resemblance (including both of the leaves, and the tall height and robust growth habit of this plant) to pokeweed (Phytolacca americana), which is not closely related. |
 Denser inflorescence with more, smaller flowers, more tightly-packed. Petals are a washed-out pink to purple color. Photo © , CC BY-SA 4.0. |  Sparser inflorescence, with fewer, larger, more loosely-packed flowers. Petals often green, occasionally pale purple. Photo © aberkov, CC BY 4.0. |
 Seedpods stouter, covered in numerous soft prickles. Seedpods may have any orientation, upright, horizontal, or even downward. Photo © Jason E. Farabaugh, CC BY 4.0. |  Seedpods narrow and usually held upright, covered in long, vertical ridges. Photo © aarongunnar, CC BY 4.0. |
 Thicker, more robust stem and foliage. Photo © Alexandra Destria, CC BY 4.0. |  Narrower stem and thinner, more delicate foliage. Photo © Evan M. Raskin, CC BY 4.0. |
 Broad, ovate leaves with rounded tips and bases, with numerous prominent side-veins. Photo © Chase G. Mayers, CC BY 4.0. |  Leaves taper more both at tip and base, and have fewer prominent side-veins. Photo © Sandy Wolkenberg, CC BY 4.0. |
References & External Resources
These short lists show only links helpful for ID. For a complete list of references and resources also covering other aspects of ecology, visit the links section of the full article on each plant, whcih is the first entry here.
