Aconogonon davisiae

(W. H. Brewer ex A. Gray) Soják

Preslia46: 151. 1974

Common names: Davis’s knotweed
Synonyms: Aconogonon newberryi Polygonum newberryi
Basionyms: Polygonum davisiae
Found in FNA Volume 5. Treatment on page 599. Mentioned on page 598.
Plants 12–42(–50) cm. Stems ascending to erect, glabrous or pubescent. Leaves: ocrea reddish brown, funnelform, 0.3–3 cm, margins oblique, glabrous or finely pubescent to pilose; petiole 0.3–10(–15) mm; blade oblong-ovate to ovate, rarely broadly lanceolate, 2.1–7.5(–9.5) × 1.1–5 cm, subcoriaceous, base truncate or, rarely, cordate, margins entire, glabrous or ciliate, apex obtuse to acute, faces often glaucous, glabrous or pubescent. Inflorescences axillary, racemelike; peduncle essentially absent. Pedicels 0.5–1.9(–2.4) mm. Flowers 1–4 per ocreate fascicle, rarely some flowers with stamens poorly developed; perianth greenish to pinkish white, 2–4.5 mm; tepals slightly dimorphic or, rarely, distinctly so, oblong-ovate to obovate, apex obtuse; anthers yellow or pink. Achenes exserted, yellowish brown, not beaked distally, 3.2–6(–8.3) × 2.1–5 mm, shiny, faces not concave. 2n = 20.

Distribution

w United States.

Discussion

Varieties 2 (2 in the flora).

The varieties are largely sympatric and often intergrade. The treatment here follows Hong S. P. (1991).

References

None.

Key

1 Faces of leaf blades pubescent, rarely glabrescent Aconogonon davisiae var. davisiae
1 Faces of leaf blades glabrous Aconogonon davisiae var. glabrum
Facts about "Aconogonon davisiae"
AuthorHarold R. Hinds† + and Craig C. Freeman +
BasionymPolygonum davisiae +
Common nameDavis’s knotweed +
IllustratorYevonn Wilson-Ramsey +
ReferenceNone +
SynonymAconogonon newberryi + and Polygonum newberryi +
Taxon nameAconogonon davisiae +
Taxon parentAconogonon +
Taxon rankspecies +
VolumeVolume 5 +