Aconogonon alaskanum

(Small) Soják

Preslia 46: 150. 1974.

Common names: Alaska wild-rhubarb
Illustrated
Basionym: Polygonum alpinum var. alaskanum Small Monogr. Amer. Sp. Polygonum, 33. 1895
Synonyms: Polygonum alaskanum (Small) W. Wight ex Harshberger Polygonum alpinum subsp. alaskanum (Small) S. L. Welsh
Treatment appears in FNA Volume 5. Treatment on page 598.

Plants (30–) 50–150 (–200) cm. Stems erect, glabrous or densely and retrorsely pubescent. Leaves: ocrea reddish-brown, funnelform, 1–2.2 cm, margins oblique, glabrous or pilose; petiole 0.8–3.5 (–4) mm; blade narrowly lanceolate to ovate, 5–20 × 2–8 cm, not subcoriaceous, base truncate or obtuse to subcordate, margins sometimes irregularly undulate, ciliate or, rarely, glabrous, apex acuminate, faces not glaucous, glabrous or pubescent. Inflorescences terminal, sometimes also axillary, paniclelike; peduncle 0–4 cm, glabrous or pubescent. Pedicels 0.5–0.1 mm. Flowers 2–4 per ocreate fascicle, all flowers with stamens well developed; perianth white or greenish white, 2–4 mm; tepals dimorphic, rarely slightly so, ovate, apex obtuse; anthers yellow to pink. Achenes included or exserted, tan to grayish brown, not beaked distally, 2.6–3.8 × 2–3 mm, shiny, faces usually not concave. 2n = 20.

Distribution

V5 1215-distribution-map.gif

N.W.T., Yukon, Alaska, Europe (e Russia)

Discussion

Varieties 2 (2 in the flora).

Aconogonon alaskanum has been considered conspecific with the morphologically similar Eurasian A. alpinum (Allioni) Schur, but the taxa differ in leaf size and achene characters. Nomenclatural issues were clarified by J. T. Kartesz and K. N. Gandhi (1990) and K. L. Chambers (1992).

Selected References

None.

Key

1 Leaf blades pubescent; stems usually densely and retrorsely pubescent Aconogonon alaskanum var. alaskanum
1 Leaf blades glabrous except for margins; stems mostly glabrous, rarely pubescent proximal to nodes Aconogonon alaskanum var. glabrescens

"/2" is not declared as a valid unit of measurement for this property.

... more about "Aconogonon alaskanum"
tan;grayish brown +
0.26 cm2.6 mm <br />0.0026 m <br /> (0.38 cm3.8 mm <br />0.0038 m <br />) +
exserted +  and included +
3-gonous +
yellow +  and pink +
ovate +  and elliptic +
Harold R. Hinds† +  and Craig C. Freeman +
(Small) Soják +
obtuse +  and subcordate +
Polygonum alpinum var. alaskanum +
5 cm50 mm <br />0.05 m <br /> (20 cm200 mm <br />0.2 m <br />) +
narrowly lanceolate;ovate +
2cm;8cm +
foliaceous +  and perfoliate +
scale-like +
just below the soil surface or and above the soil surface +  and spreading +
Alaska wild-rhubarb +
N.W.T. +, Yukon +, Alaska +  and Europe (e Russia) +
pubescent +, glabrous +  and not glaucous +
concave +
adnate +, free +  and distinct +
disarticulating +  and solid +
decumbent to erect +  and prostrate +
unwinged +  and winged +
black +, red +, brown +  and yellowish +
exserted +  and included +
pubescent +  and glabrous +
spheroidal +, 4-gonous +, lenticular +, biconvex +, discoid +, 3-gonous +  and 2-gonous +
compound +, branched +  and simple +
nonmembranous +
sessile +  and petiolate +
deciduous +
glabrous +  and pilose +
undulate +
swollen +
partly +  and foliaceous +
reddish-brown +
deciduous +  and persistent +
cylindric +
1 cm10 mm <br />0.01 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
coriaceous +  and membranous +
anatropous +, , +  and orthotropous +
accrescent +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.01 cm0.1 mm <br />1.0e-4 m <br />) +
pubescent;glabrous +
0 cm0 mm <br />0 m <br /> (4 cm40 mm <br />0.04 m <br />) +
nonaccrescent +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
fleshy +, indurate +  and membranous +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
(2-)3(-4)-carpellate +
slender;stout +
Illustrated +
not scapose +
penicillate +, fimbriate +  and capitate +
deciduous +  and persistent +
? (?) +  and ? (?) +
coriaceous +  and membranous +
connate +  and distinct +
spreading;erect +
Polygonum alaskanum +  and Polygonum alpinum subsp. alaskanum +
Aconogonon alaskanum +
Aconogonon +
species +
coriaceous +
persistent +
membranous +
pubescent +  and glabrous +
11 +, 10 +  and 8 +