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Photo is of parent taxon

Davis' knotweed, Newberry's fleeceflower, Newberry's knotweed

Habit Plants 12–42(–50) cm.
Stems

pubescent, rarely glabrescent.

ascending to erect, glabrous or pubescent.

Leaves

blades 2.1–7.5(–9.5) × 1.1–5 cm, base truncate or, rarely, cordate, faces pubescent, rarely glabrescent.

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

0.5–1.7(–2.4) mm, glabrous.

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.

Perianths

2–4.5 mm.

Achenes

exserted, yellowish brown, not beaked distally, 3.2–6(–8.3) × 2.1–5 mm, shiny, faces not concave.

2n

= 20.

= 20.

Aconogonon davisiae var. davisiae

Aconogonon davisiae

Phenology Flowering Jun–Aug.
Habitat Steep subalpine slopes, volcanic fell fields, often on talus or pumice
Elevation 1200-3100 m (3900-10200 ft)
Distribution
from FNA
CA; ID; OR; WA
from FNA
CA; ID; OR; WA
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

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

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Faces of leaf blades pubescent, rarely glabrescent
var. davisiae
1. Faces of leaf blades glabrous
var. glabrum
Source FNA vol. 5, p. 600. FNA vol. 5, p. 599.
Parent taxa Polygonaceae > subfam. Polygonoideae > Aconogonon > Aconogonon davisiae Polygonaceae > subfam. Polygonoideae > Aconogonon
Sibling taxa
A. davisiae var. glabrum
A. alaskanum, A. phytolaccifolium
Subordinate taxa
A. davisiae var. davisiae, A. davisiae var. glabrum
Synonyms Polygonum davisiae, A. newberryi, Polygonum newberryi
Name authority unknown (W. H. Brewer ex A. Gray) Soják: Preslia 46: 151. (1974)
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