Garlic Mustard

Plant: Upright, annual or biennial forb, in small to extensive colonies, basal rosettes of leaves in first year (remaining green during winter) becoming 2-4 ft (61-125 cm) tall in second year, faint to strong garlic odor from all parts of the plant when crushed, with plants dying after mid-summer, standing dried plants after June with long-slender seed stalks, from a rootstock with white slender taproot and characteristic crook at the top of the root.

Stem: Erect, slightly ridged, hairless above and hairy below, 1-several stems from the same rootstock.

Leaves: Early basal rosette and later alternate, kidney-shaped in basal rosette and heart-shaped to triangular on stem, 1.2-3.5 in (3-9 cm) long and 1-4 in (2.5-10 cm) wide, margins shallow to coarsely toothed, petioles 0.4-3 in (1-8 cm) long and shortest upward, emit garlic odor when crusted but less so approaching fall.

Flowers: Apr-May. Terminal, tight clusters of small white flowers, 4-petaled, each 0.2-0.3 in (5-7 mm) long.

Fruit and seeds: May-Jun. Thin pod, 1-5 in (3-13 cm)