Scientific Name: Nuttallanthus canadensis

Common Name: Canada toadflax

Other Common Names: old-field toadflax

Synonyms: Linaria canadensis

Habit: Grows from 6-24 inches tall and blooms from April to September.

Leaves: Stems are up to 50 cm tall, erect, single or multiple from base, and typically simple or branching. Leaves of flowering stems are alternate, linear, and wispy, up to 3.5 cm long and 3 mm wide, with margins slightly thickened.

Identifying Characteristics: It is identified by its irregular blue flowers, its small thin leaves, and its basal spurs.

Flower Seed Head: Flowers are 1/4-1/2 inch long, pale blue-purple with lighter palate, small, on top of slender stalks, spurred, pubescent internally. Upper lip erect, 2-lobed, and 5-6mm long. Lower lip 8mm long, 1.3cm broad, glabrous, and 3lobed. Lobes to 3mm long, 1mm broad (in flower), linear-oblong, acute, green, glandular pubescent.

Seed Fruit: Fruits are capsules 3mm long and broad, many seeded, and glabrous.

Where Found: Dry, sandy, or rocky soil, abandoned fields, roadsides, open ground, glades, bluffs, prairies, and railroads.

  • Life cycle: biennial

  • Milky sap: Not Present

  • Plant type: Herb

  • Thorns: Not Present

  • Plant family: Scrophulariaceae

  • Leaf arrangement: alternate; whorled; opposite

  • Leaf shape: oval; spatulate

  • Ochrea: Not Present

  • Leaf margin: entire

  • Stem hairs: no hairs

  • Flower color: blue; white; purple

  • Growth habit: upright and nonwoody

  • Stem: round or oval

  • Leaf hairs: no hairs

  • Flower diameter: dime; pencil

  • Flower symmetry: bilateral symetry

  • Root structure: fibrous; taproot