Flora of North America species comparison

erect to ascending, unbranched proximally, few to many branches above middle, conspicuously sulcate.

erect, usually multiple from base, unbranched proximal to inflorescence.

proximal 0–13 pairs opposite (often fallen at anthesis), distal alternate, appressed-ascending;

stipular glands usually present, very rarely absent;

blade linear to narrowly lanceolate, 7–30 × 1–3 mm, margins entire, distal leaves not ciliate, apex acute to subulate;

midrib prominent, marginal nerves less conspicuous.

proximal 3–20 pairs opposite, distal alternate, rarely (in northern plants) opposite nearly to inflorescence, erect to appressed;

stipular glands absent;

blade narrowly lanceolate to oblanceolate, 10–25 × 1.5–5.5 mm, margins entire, not ciliate, apex obtuse or apiculate.

open panicles;

bracts glandular-toothed, not ciliate.

corymbs.

1.3–4.7 mm.

0–5 mm.

sepals persistent, lanceolate, (3.1–)3.6–5(–7.3) mm, inner sepals more delicate than outer, shorter, margins not scarious, all very conspicuously glandular-toothed, apex acuminate, central and marginal veins conspicuous;

petals pale yellow, obovate, 5–10 mm;

stamens 3.3–5.7 mm;

anthers 0.3–0.7 mm;

staminodia absent;

styles connate 0.2–1.8 mm at base, 2–4.5 mm;

stigmas capitate.

sepals persistent, lanceolate, inner somewhat shorter, broader than outer, outer sepals 2–5 mm, margins not scarious, inner usually glandular-toothed, rarely entire, outer entire, apex acute;

petals lemon yellow, obovate, 4.5–8 mm;

stamens 2.5 mm;

anthers 0.5–l.3 mm;

staminodia absent;

styles distinct, 1–3 mm;

stigmas capitate.

globose, 2.5–3.3 × 2.1–3 mm, apex rounded to acute, dehiscing freely into 10, sharp-pointed, 1-seeded segments;

segments persistent on plant, false septa incomplete, margins prominently ciliate.

depressed-globose, 1.6–2.3 × 2–2.5 mm, apex depressed, tardily (or readily in var. medium) dehiscing into 10, 1-seeded segments, segments usually persistent on plant, false septa nearly complete, proximal margins not ciliate.

1.6–2.1 × 0.8–1.1 mm.

1.3–1.7 × 0.6–0.8 mm.

= 30.