Leaves bi- to tri-pinnate, dark green, appressed-hairy on both surfaces, longipetiolate: lobes mostly 10–20 millimetres (0.39–0.79 in), ovate in outline, deeply toothed, the teeth contracted abruptly at the apex.

[8] Chaerophyllum temulum contains (mainly in the upper parts and fruits) a volatile alkaloid chaerophylline, as well as other (probably glycosidally bound) toxins, the chemistry and pharmacology of which has, as yet, been but little studied[citation needed].

Human poisonings have seldom been observed, because the plant lacks aromatic essential oils that could lead to its being confused with edible umbellifers used to flavour food.

Animal poisonings by the plant are commoner than those of humans, pigs and cattle thus intoxicated exhibiting a staggering gait, unsteady stance, apathy and severe, exhausting colic, ending sometimes in death.

[9] Chaerophyllum temulum has been used in folk medicine, in small doses, to treat arthritis, dropsy, and chronic skin complaints, and as a spring tonic.

The early modern physician Boerhaave (1668–1738) once successfully used a decoction of the herb combined with Sarsaparilla to treat a woman suffering from leprosy – in the course of which treatment temporary blindness was a severe side effect following each dose.