Aconogonon phytolaccifolium

(Meisner ex Small) Small

in P. A. Rydberg, Fl. Rocky Mts., 1061. 1917.

Common names: Poke knotweed
Endemic
Basionym: Polygonum phytolaccifolium Meisner ex Small Bull. Torrey Bot. Club 19: 360. 1892
Treatment appears in FNA Volume 5. Treatment on page 599. Mentioned on page 598.

Plants (50–)70–150(–200) cm. Stems erect, glabrous or pubescent. Leaves: ocrea reddish brown, funnelform, 1–3 cm, margins oblique, glabrous or pubescent; petiole 5–20 mm; blade lanceolate to ovate-lanceolate, 5–15(–19) × 1.4–7.5 cm, not subcoriaceous, base rounded, margins entire, usually scabrous to ciliate, rarely glabrous, apex obtuse to acuminate, faces not glaucous, glabrous or densely pubescent. Inflorescences usually terminal, subterminal, and axillary, paniclelike; peduncle 0.5–12 cm, glabrous or pubescent. Pedicels 0.9–4 mm. Flowers 1–3 per ocreate fascicle, rarely some flowers with stamens poorly developed; perianth white to greenish white, 2.5–3.5 mm; tepals slightly dimorphic, ovate to obovate, apex obtuse; anthers yellow to pink. Achenes usually exserted, yellowish brown, not beaked distally, (3–)3.8–7 × 2.3–4.8 mm, shiny, faces concave.

Distribution

V5 1218-distribution-map.gif

Calif., Idaho, Mont., Nev., Oreg., Wash.

Discussion

Varieties 2 (2 in the flora).

Selected References

None.

Key

1 Stems glabrescent or pubescent; leaf blade margins scabrous to ciliate Aconogonon phytolaccifolium var. phytolaccifolium
1 Stems glabrous; leaf blade margins glabrous Aconogonon phytolaccifolium var. glabrum