Linaria genistifolia subsp. genistifolia
Perennials, reproducing vegetatively by rhizomes. Fertile stems usually erect, 18–60 cm; sterile stems usually absent. Leaves of fertile stems: blade lanceolate or linear-lanceolate, flat, 5–45 (–85) × 2–10 (–35) mm, apex acute. Racemes 5–26-flowered, lax; bracts lanceolate, 3–10 × 1–2 mm. Pedicels erect-patent to erect, 2–4 mm in flower, 3–8 mm in fruit. Calyx lobes ovatelanceolate to lanceolate, 2.5–5 × 0.7–1.5 mm in flower, 3–6 × 0.8–1.7 mm in fruit, apex acute. Corollas pale to bright-yellow, 16–20 (–23) mm; tube 4–5 mm wide, spurs straight, 7–9 (–10) mm, slightly shorter or subequal to rest of corolla, abaxial lip sinus 2–3 mm, adaxial lip sinus 2–3.5 mm. Styles simple; stigma entire. Capsules subglobular, 4–5 × 4–4.8 mm, glabrous; loculi equal. Seeds black or blackish brown, subtrigonous or ± tetrahedral, 0.8–1.2 (–1.4) × 0.6–1 mm, with longitudinal marginal ridges and anastomosed ridges or tubercles on faces; wing absent. 2n = 12 (Europe).
Phenology: Flowering Jul–Sep.
Habitat: Roadsides, disturbed places.
Elevation: 0–2100 m.
Distribution
Introduced; Mass., Minn., N.Y., Ohio, Oreg., Utah, Wash., se Europe
Discussion
Collections of subsp. genistifolia on ballast are known from New York (pre-1900) and Oregon (1912).
Selected References
None.