5. Amsonia tabernaemontana Walter, Fl. Carol. 98. 1788.
[E]
Eastern blue-star
Stems erect (ascending), 27–102 cm, glabrous (sparsely pubescent); branches borne on distal portion of stem, much exceeding infructescence. Leaves: petiole 1.5–7(–9) mm, sparsely to moderately pubescent or glabrous; blades not heteromorphic; stem leaf blades lanceolate to narrowly lanceolate, ovate, narrowly elliptic, or elliptic, (2.5–)3.3–12.5(–14.4) cm × (8–)11–50(–65) mm, margins entire to subentire, not to moderately revolute, ciliate or not, apex acuminate to acute (rarely with a rounded tip), surfaces sparsely pubescent abaxially (and sparsely scabrous or short-pubescent adaxially) or glabrous; branch leaf blades similar to stem leaf blades. Flowers: sepals deltate to narrowly deltate, (0.4–)0.5–1.8(–2.3) mm; corolla tube bluish (rarely to lilac), sometimes greenish above, (5–)6–8(–8.8) mm, lobes pale blue (rarely to dark or lilac-blue or white), (5–)6–9.8(–12) mm, outer surface of corolla with 5 patches of long trichomes at corolla lobe bases and distal part of tube (very rarely glabrate). Follicles erect to pendulous (spreading), (5–)7–15 cm × 2.1–4(–4.2) mm, apex acuminate (acute), glabrous. Seeds (5–)5.5–10.8 × (1.2–)1.5–2.4(–3.3) mm.
Varieties 4 (4 in the flora): c, e United States.
Amsonia tabernaemontana encompasses a great deal of morphological diversity, particularly in leaf size and shape and sepal indument and length, which is to some extent geographically correlated; therefore, the recognition of varieties seems desirable. However, the varieties are not well differentiated and tend to blend into one another, especially where their ranges overlap.