Hedge parsley is an introduced plant that looks a lot like cultivated parsley. It was first collected in Missouri in 1909 and has become much more abundant in recent decades as it spreads along roadsides and railroads.
Hedge parsley is a much-branched, hairy annual, with flat-topped clusters raised well above the foliage. The stems are have fine white hairs that appear pressed against the surface.
The flowers are on long stems (peduncles), white, in umbels (umbrella-like clusters), minute, with 5 sepals and 5 petals.
Blooms June–September.
The leaves are alternate and usually also basal, 1 or 2 times feather-compound, resembling parsley. Like the stems, they have appressed white hairs.
The fruits are densely covered with hooked prickles, like tiny cockleburs, and they readily cling to clothing and fur. When young, the fruits may be tinged with pink.
Similar species: Missouri has several species in the carrot-parsley family, and all have the family's signature umbrella-like flower clusters, technically called umbels.
Height: to 2½ feet.
Scattered to common statewide.
Habitat and Conservation
Nonnative plant; occurs on banks of streams and rivers, disturbed portions of glades, upland prairies and savannas, and degenerating clear-cuts in mesic (moist) upland forests; also roadsides, railroads, old fields, and open, disturbed areas.
This species was first collected in Missouri in 1909 and has become much more abundant in recent decades as it spreads along roadsides and railroads.
Status
Nonnative wildflower. Introduced. Native of Eurasia. Considered invasive in some US states.
Human Connections
Humans literally pave the way for the spread of many weedy species when we bulldoze the earth to build roads. Fast-growing "pioneer plants," which many call weeds, quickly colonize the disturbed, bare soil and rapidly produce multitudes of seeds. Slow-growing plants take longer to become established.
This species is also a garden weed.
Ecosystem Connections
As a nonnative, introduced plant, this species does not contribute to Missouri's native natural ecosystems.
The bristly seeds cling to the fur and feathers of animals (and clothing of humans). This carries the seeds away from the parent plant and establishes populations in new areas. This may be how this plant came to Missouri in the early 1900s; think, for example, of how cattle, which might have been "wearing" the seeds on their legs, were transported across the continent on railcars during that period.
