(Silphium radula)
Rough-Stem Rosinweed

Rough-stem Rosinweed (Silphium radula)

Rough-Stem Rosinweed (Silphium radula), a member of the Asteraceae (Aster Family), is a herbaceous perennial that grows from 1′ to 10′ tall and blooms with yellow flowers in the summer to early fall (July to September).  This plant grows in places with full sun that have dry circumneutral well-drained soils, but can handle moist soil and is hardy in zones 3-9.  More information on this species can be found on this blog post.

Hosted Species

This species hosts the Bordered Patch Butterfly (Chlosyne lacinia) in the western part of its range and the silphius borer moth (Papaipema silphii), throughout.

Nectar Species

This species is a nectar source to other butterflies, skippers, bees, and wasps during the growing season.  Birds, such as goldfinch, like to eat the seeds in the fall.

Habitat

This rosinweed grows in open areas such as prairies, roadsides, and riparian areas.

Range of Rough-Stem Rosinweed (Silphium radula) in the United States and Canada

Origin of the Name

The genus name, Silphium, is derived from the Greek word that originated from a resin-bearing plant (Missouri Botanical Garden).  The species name, radula, is Latin for teeth, referring to the lower leaf margins.