Eriogonum mancum

Rydberg

Fl. Rocky Mts., 220, 1061. 1917.

Common names: Imperfect wild buckwheat
Endemic
Synonyms: Eriogonum chrysocephalum subsp. mancum (Rydberg) S. Stokes
Treatment appears in FNA Volume 5. Treatment on page 278. Mentioned on page 230, 234, 240, 241.

Herbs, matted, scapose, 0.5–1 (–1.3) × 1–2 dm, tomentose, grayish. Stems spreading, with persistent leaf-bases, up to 1/5 height of plant; caudex stems matted; aerial flowering-stems scapelike, weakly erect to erect, slender, solid, not fistulose, 0.1–0.9 (–1.2) dm, tomentose. Leaves basal, fasciculate in terminal tufts; petiole 0.5–1 cm; blade oblanceolate to spatulate or ovate, 0.5–1.5 (–1.8) × (0.2–) 0.3–1 cm, densely grayish-tomentose on both surfaces, margins plane. Inflorescences capitate, 0.8–1.2 cm; branches absent; bracts 3–5, scalelike, triangular, 1–3 mm. Peduncles absent. Involucres 2–5 per cluster, campanulate, 2–3 (–3.5) × 2–3.5 (–4) mm, membranous, tomentose; teeth 5, erect, 0.4–0.8 mm. Flowers 2–3 mm; perianth cream to pink or rose, glabrous or sparsely pilose, pustulose; tepals connate proximal 1/4–1/3, monomorphic, oblong; stamens exserted, 2–2.5 mm; filaments pilose proximally. Achenes light-brown, (2–) 2.5–3 mm, glabrous except for minutely papillate beak.


Phenology: Flowering May–Jul.
Habitat: Gravelly to clayey flats and slopes, mixed grassland, saltbush, sagebrush, and mountain mahogany communities, juniper woodlands
Elevation: 1100-2000 m

Discussion

Eriogonum mancum is widely scattered in Butte, Clark, Custer, and Lemhi counties of southeastern Idaho, in Beaverhead, Broadwater, Carbon, Deer Lodge, Gallatin, Granite, Jefferson, Lewis and Clark, Madison, Powell, Ravalli, and Silver Bow counties in western Montana, and in Big Horn County of northwestern Wyoming. It is disjunct on limestone outcrops in the House Range of Millard County, Utah, no doubt a Pleistocene relic.

Plants from the rim of Little Mountain west of Kane, Big Horn County, Wyoming (B. E. Nelson 5407, BRY, MARY, NY, RM, UTC), and those just to the north in southern Carbon County, Montana (Lesica 2632, 5379, 5405, 5439, and 5453, MONTU), have tepals with a few long, pilose hairs along the midrib adaxially. These populations are well isolated from others of the species, but the taxonomic significance of this expression has yet to be determined.

Selected References

None.

Lower Taxa

None.

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... more about "Eriogonum mancum"
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
light-brown +
included +  and exserted +
3-gonous +
usually red +  and cream or yellow +
oblong +  and ellipsoid or oval +
acute;obtuse or rounded +
James L. Reveal +
Rydberg +
deciduous +  and persistent +
stipelike +
Undefined subg. Eucycla +
papillate +
awn-tipped +  and simple +
1.5 cm15 mm <br />0.015 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
grayish-tomentose +
oblanceolate;spatulate or ovate +
0.3 cm3 mm <br />0.003 m <br /> (1 cm10 mm <br />0.01 m <br />) +
not awn-tipped +
leaflike +  and semileaflike +
glandular +, pubescent +  and glabrous +
triangular +  and scale-like +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
grooved +, branched +  and open +
not brittle +
spreading +  and erect +
tomentose +  and floccose or glabrous occasionally lanate or glandular +
scabrellous +
ridged +, angled +  and round +
spreading +  and erect +
whorled +, opposite +  and alternate +
Imperfect wild buckwheat +
Idaho +, Mont. +, Utah +  and Wyo. +
1100-2000 m +
unisexual +, , +  and bisexual +
not attenuate +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
decumbent to erect +  and prostrate +
not fistulose +
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 +
Gravelly to clayey flats and slopes, mixed grassland, saltbush, sagebrush, and mountain mahogany communities, juniper woodlands +
reduced +
open +, virgate +, umbellate +, cymose-umbellate +  and cymose +
dense +  and diffuse +
cymelike +, paniclelike +, racemelike +  and spikelike +
0.8 cm8 mm <br />0.008 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
connate +  and free +
0.3 cm3 mm <br />0.003 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
campanulate +
0.2 cm2 mm <br />0.002 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
in whorls +, opposite +, alternate +  and rosulate +
persistent +
bractlike +
pubescent +  and glabrous +
not swollen +
orthotropous +
accrescent +
curved +  and straight +
erect to deflexed +
cream;pink or rose +
pilose +  and glabrous +
cylindric +  and urceolate +
accrescent +
fleshy +, indurate +  and membranous +
with extrafloral nectaries +  and not articulate +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
Flowering May–Jul. +
homostylous +  and 3-carpellate +
Fl. Rocky Mts., +
, +  and solid +
slender;stout +
persistent +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
decumbent to erect +  and prostrate +
glandular +, pubescent +  and glabrous +
penicillate +, fimbriate +  and capitate +
deciduous +  and persistent +
2-lobed +  and cylindric +
coriaceous +  and membranous +
consisting of a series +  and tubular +
distinct +
erect;spreading or recurved +
spreading;erect +
Eriogonum chrysocephalum subsp. mancum +
chambered +  and solid +
slender +  and stout +
Eriogonum mancum +
Eriogonum subg. Eucycla +
species +
emarginate +  and entire +
0 +  and 1/2 +
1/4 +  and 1/3 +
coriaceous +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
persistent +
membranous +
pubescent +  and glabrous +
herb +  and matted +
synoecious +, monocarpic +, polycarpic +  and , +
3 +, 2 +  and 1 +