2. Agrimonia parviflora Aiton (swamp agrimony, many-flowered agrimony, harvest lice)

Pl. 523 f, g; Map 2402

Roots usually all fibrous (rarely tuberous-thickened). Stems 30–120(–200) cm long, glandular and densely pubescent with short, ascending and long, spreading hairs, the hairs becoming sparser toward the tip. Leaves 3–30 cm long, the median and lower leaves with the primary (larger) leaflets 11–23, these 1.5–7.0 cm long, mostly narrowly elliptic or lanceolate, tapered to a sharply pointed tip, the margins with mostly relatively sharply pointed teeth, the upper surface glabrous or nearly so, the undersurface glandular and sparsely to moderately short-hairy, especially along the veins, sometimes also with sparse, longer, spreading hairs. Inflorescence axis glandular and pubescent with short ascending and often also sparse, long, spreading hairs. Stamens 5–10. Hypanthium at fruiting 2–3 mm long (4–5 mm long, including the beak), deeply grooved, glandular, sometimes also sparsely hairy along the ridges. 2n=56. July–August.

Scattered nearly throughout the state, but apparently absent from portions of northwestern and southeastern Missouri (eastern U.S. west to South Dakota and Texas; Canada, Mexico, Caribbean Islands). Bottomland forests, mesic upland forests in ravines, banks of streams and spring branches, swamps, fens, bottomland prairies, upland prairies; also roadsides, ditches, margins of crop fields, and moist disturbed areas.

In addition to having leaves with more primary leaflets, the inflorescences of this species tend to have more and denser flowers than in other Missouri agrimonies.