Bur chervil (Anthriscus caucalis) is native to Eurasia, however, since being introduced as a garden ornamental, this annual has naturalized throughout large portions of North America. Found along stream banks and in other open moist places, bur chervil smells like parsley when crushed. It is a member of the Carrot (or Parsley) Family.
Bur chervil stems can grow up to three feet in height and are somewhat branched, hollow and hairy near the base. The alternate leaves are finely divided into many leaflets and appear lacy and fern-like.
The white, five-petaled flowers are borne in few-flowered, compound umbels (inflorescence in which the flower stalks arise from one point on the stem). Bract-like leaves surround the umbel. The petals are attached at the top of the inferior ovary just below an enlargement at the base of the styles (stylopodium).
The fruit of bur chervil is covered with velcro-like, hooked, minute bristles. The fruit splits into two units, each containing one seed, at maturity. Aggressively reproducing by seed, bur chervil is considered a noxious weed.
Bur chervil can cause skin irritation.
Other common names for A. caucalis are bur beakchervil and burr chervil. Formerly, bur chervil was classified as Anthriscus scandicina.
These bur chervil specimens were photographed on the levee between Baum and Crystal Lakes in Shasta County CA.