Flora of North America species comparison

green, brown, or purple, pubescent or hispid-hirsute, occasionally glabrous, usually densely covered with short, glandular trichomes;

thorns 1 or 2 per node or absent, 4–30 × 0.4–2 mm.

blades ovate to lanceolate, occasionally linear, 1–12 × 0.2–3 cm, base attenuate to acute, margins entire or serrulate, surfaces puberulent to hispid-hirsute, with or without glandular trichomes.

terminal, narrow or broadly branching, leafy panicles or clustered at branch tips, 20–100-flowered.

sepals lanceolate, 6–14 × 1.5–3.5 mm, puberulent to hispid-hirsute, with glandular trichomes;

corolla blue, rarely white, petals 5–17 × 2–12 mm;

ovary puberulent, upper 1/2 usually glandular-pubescent;

styles 2–4, 1.5–13 mm, glandular-pubescent toward bases.

globose to ovoid, 3.5–8 × 3–7 mm, upper 1/2 puberulent or glandular-pubescent.

ovoid to cylindric, symmetric, 0.4–0.7 × 0.2–0.3 mm.

= 20, 40.