Polygonum utahense

Brenckle & Cottam

Bull. Univ. Utah, Biol. Ser. 4(4): 3, plate 1. 1940.

Common names: Utah knotweed
Synonyms: Polygonum douglasii var. utahense (Brenckle & Cottam) S. L. Welsh
Treatment appears in FNA Volume 5. Treatment on page 571. Mentioned on page 561, 562.

Herbs. Stems erect, green, simple or with few branches, not wiry, 1.5–3.5 cm, papillose-scabridulous. Leaves uniformly distributed, articulated to ocreae, basal leaves persistent, distal leaves abruptly reduced to bracts; ocrea 2–3.5 mm, papillose-scabridulous, proximal part funnelform, distal part hyaline, lacerate; petiole absent; blade 1-veined, not pleated, linear-subulate, 6–14 × 1 mm, coriaceous, margins revolute, touching along midrib, apex acute, mucronate, papillose. Inflorescences axillary and terminal, spikelike, dense; cymes overlapping, starting almost from stem base, 2–4-flowered. Pedicels enclosed in ocreae, erect to spreading, 0.4–1 mm. Flowers open; perianth 2–2.5 mm; tube 20–25% of perianth length; tepals overlapping, uniformly white, petaloid, oblong to widely obovate, cucullate, navicular in distal 1/4, apex rounded; midveins branched; stamens 8. Achenes enclosed in perianth, black, elliptic, 1.5–2 mm, faces subequal, shiny, smooth.


Phenology: Flowering Jul–Sep.
Habitat: Dry, sandy ravines, rocky Navajo sandstone spur
Elevation: 2300 m

Discussion

Polygonum utahense has been treated as a synonym of P. sawatchense by some authors (e.g., S. L. Welsh et al. 1987; J. T. Kartesz and C. A. Meacham 1999). Its perianth morphology suggests a relationship with P. cascadense, from which it differs in its dwarf habit and uniformly papillose leaves with margins revolute, touching along midribs.

Selected References

None.

Lower Taxa

None.

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

... more about "Polygonum utahense"
reticulate +, tubercled +  and smooth +
exserted +  and included +
dull +  and shiny +
3-gonous +, ovate +  and elliptic or lanceolate +
pink +  and purple +
elliptic +  and oblong +
papillose +
rounded;mucronate;acute +
Mihai Costea +, François J. Tardif +  and Harold R. Hinds† +
Brenckle & Cottam +
not stipelike +
0.6 cm6 mm <br />0.006 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
linear-subulate +
coriaceous +
1 cm10 mm <br />0.01 m <br /> (?) +
foliaceous +  and perfoliate +
scale-like +
just below the soil surface or and above the soil surface +  and spreading +
Utah knotweed +
2-4-flowered +
overlapping +
2300 m +
subequal +
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 +
Dry, sandy ravines, rocky Navajo sandstone spur +
compound +, branched +  and simple +
nonmembranous +
articulated +
distributed +
deciduous +
not rugulose +
papillose-denticulate +
swollen +
silvery +, white +  and hyaline +
disintegrating +
deciduous +  and persistent +
papillose-scabridulous +
0.2 cm2 mm <br />0.002 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
coriaceous +  and membranous +
somewhat larger +
anatropous +, , +  and orthotropous +
erect;spreading +
accrescent +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
spreading;erect +
greenish white;pink +
campanulate +  and urceolate +
nonaccrescent +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
fleshy +, indurate +  and membranous +
not +  and articulated +
Flowering Jul–Sep. +
(2-)3(-4)-carpellate +
Bull. Univ. Utah, Biol. Ser. +
papillose-scabridulous +  and smooth +
slender;stout +
woody +  and fibrous +
not wiry +, with few branches +  and simple +
zigzagged +  and straight +
papillose-scabridulous +
4-gonous +
1.5 cm15 mm <br />0.015 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
2 +  and 3 +
penicillate +, fimbriate +  and capitate +
deciduous +  and persistent +
2-lobed +  and cylindric +
coriaceous +  and membranous +
connate +  and distinct +
spreading;erect +
Polygonum douglasii var. utahense +
Polygonum utahense +
Polygonum sect. Duravia +
species +
overlapping +
connate +  and distinct +
navicular +, cucullate +, oblong +  and widely obovate +
coriaceous +
persistent +
membranous +
pubescent +  and glabrous +
heterophyllous +  and homophyllous +