Stems & Roots: Stems erect, little or not branched, 10-150cm (4-60in.) tall or occasionally much taller, smooth, hairless, firm; first leaves of young plant in a basal rosette, short-stalked, pinnately divided and redivided, the final divisions coarsely and sharply toothed; stem leaves similar to basal leaves but usually only once-divided with each division coarsely and sharply toothed, alternate (1 per node); by flowering time the lower stern leaves usually dying, and the basal rosette of leaves gone, only their scars remaining
Flowers & Fruit: Flower heads greenish and inconspicuous, clustered on many short branches in the axils of small leaves towards the top of the stem, forming a slender, elongate inflorescence; each individual flower head very small, about 2mm (1/12in.) across, yellowish-green, without ray florets; seeds numerous and very small. Upper leaves, stem and flower heads, and to a lesser extent the basal leaves, when crushed have an odour resembling a combination of sage and carrot. Flowers from August to October.
Habitat: Biennial wormwood occurs throughout Ontario in old fields, waste places, fence lines, meadows, around buildings, and occasionally in cultivated land.