Poison Hemlock, Conium maculatum
Family: Apiaceae; Parsley Famiy
Vegetative Characteristics:
Seedling: cotyledons oblong-lanceolate; first leaf pinnately compound, reddish, glabrous
Stems: erect, 1.0-3.0 m tall, branching, stout, glabrous, purple-spotted, ridged, hollow except at nodes
Leaves: basal rosette; alternate upward, petioled, broadly triangular-ovate in outline, three or four times pinnately compound; leaflets lanceolate to ovate-oblong, dentate or finely cut
Reproductive Characteristics:
Inflorescences: small and white in large, open compound umbels, terminal inflorescence blooming first but soon overtopped by others; petals 5, 1.0-1.2 mm long, 0.8-1.0 mm wide, white
Fruits: schizocarp with 2 mericarps, 2.0-4.0 cm long, grayish brown, conspicuous, wavy, somewhat knotted ridges, lacking oil tubes
Seeds: encapsulated in fruit
Special Identifying Features:
⇒ erect, stoutly branching biennial; plant resembles wild carrot, parsnip, or hogweed; purple spots on stems; highly poisonous; herbage has a mouselike odor
