Linaria canadensis (Linnaeus) Dumont de Courset. Common name: Common Toadflax. Phenology: Mar-Aug; Apr-Nov. Habitat: In a wide variety of natural and disturbed habitats, especially common and weedy in disturbed sites such as roadsides and fields, also common and apparently native in thin soil of rock outcrops. Distribution: NS west to ND, south to s. FL and TX; also adventive on the west coast, from WA to CA.
Origin/Endemic status: Native
Taxonomy Comments: Sutton (1988) comments that there is substantial variation in this species not taxonomically explained.
Synonymy ⓘ: = Fl6, K4, Pa, Tx, WH3, WV, Pennell (1935), Yousefi, Heubl, & Zarre (2017); = canadensis var. — C, F, G, GrPl, S; = Nuttallanthus canadensis (L.) D.A.Sutton — Ar, FNA17, Il, Mi, Mo3, NcTx, NE, NY, Tn, Va, Sutton (1988); < Linaria canadensis (L.) Dum.Cours. — RAB, Tat, W; < Nuttallanthus canadensis (L.) D.A.Sutton — Mex; Antirrhinum canadense Linnaeus. Basionym: Antirrhinum canadense L. 1753
Links to other floras: = Nuttallanthus canadensis - FNA17
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Heliophily ⓘ: 9
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Horticultural Information
Intro: Slender, erect annual/biennial of a wide variety of natural and disturbed, dryish habitats, especially weedy in disturbed sites such as roadsides and fields but also common and apparently native in thin soil of rock outcrops.
Stems: Stems 1-several, smooth; basal offshoots prostrate to trailing and forming overwintering rosettes.
Leaves: Basal leaves linear to oblong, to 1/3 in. long; stem leaves alternate, linear, to 1 1/4 in. long, smooth.
Inforescence:
Flowers: Flowers in a narrow raceme; blue to purple; about 1/2 in. long; bilaterally symmetric; tubular, with a slender spur and opening to 2 lips, the upper lip 2-lobed and the larger lower lip 3-lobed; the white throat has 2 ridges.
Fruits: Fruit an oval capsule.
Comments: The similar N. floridanus has a zigzag raceme and N. texanus has slightly larger flowers.
Height: 6-28 in.
plant sale text:
bloom table text:
description: Slender, erect annual/biennial of a wide variety of natural and disturbed, dryish habitats, especially weedy in disturbed sites such as roadsides and fields but also common and apparently native in thin soil of rock outcrops.
stems: Stems 1-several, smooth; basal offshoots prostrate to trailing and forming overwintering rosettes.
leaves: Basal leaves linear to oblong, to 1/3 in. long; stem leaves alternate, linear, to 1 1/4 in. long, smooth.
inflorescence:
flowers: Flowers in a narrow raceme; blue to purple; about 1/2 in. long; bilaterally symmetric; tubular, with a slender spur and opening to 2 lips, the upper lip 2-lobed and the larger lower lip 3-lobed; the white throat has 2 ridges.
fruits: Fruit an oval capsule.
comments: The similar N. floridanus has a zigzag raceme and N. texanus has slightly larger flowers.
cultural notes:
germination code:
native range: eastern North America & western U.S.
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