Eriogonum terrenatum

Reveal

Phytologia 86: 144. 2004.

Common names: San Pedro River wild buckwheat
Treatment appears in FNA Volume 5. Treatment on page 254. Mentioned on page 238.

Shrubs, sprawling to erect, not scapose, 1–4 (–5) × (1–) 2–6 (–9) dm, thinly tomentose or floccose to subglabrous, greenish. Stems spreading or erect, without persistent leaf-bases, up to 1/2 height of plant; caudex stems absent; aerial flowering-stems erect or nearly so, slender, solid, not fistulose, 0.05–0.3 dm, thinly tomentose. Leaves cauline, fasciculate; petiole 0.05–0.1 cm, glabrous; blade linear-oblanceolate or linear-elliptic, 0.3–0.8 (–1) × (0.05–) 0.1–0.2 cm, densely white-tomentose abaxially, thinly floccose or glabrous and greenish adaxially, margins rolled. Inflorescences cymose, compact, 1–3 × 1–3 cm; branches dichotomous, thinly tomentose; bracts 3, scalelike, triangular, (0.5–) 1–2 mm. Peduncles absent or erect, 0.1–0.8 (–1) cm, thinly tomentose. Involucres 1 per node, campanulate, 3–4.5 × 2.5–3.5 mm wide, thinly tomentose to subglabrous; teeth 5, erect, 0.5–1.2 mm. Flowers 3.5–4.5 (–5) mm; perianth white, glabrous; tepals connate proximal 1/3, dimorphic, those of outer whorl broadly cordate, 2–3 mm wide, apex rounded, those of inner whorl oblanceolate, 1–2 mm wide; stamens exserted, 3.5–4.5 mm; filaments pilose proximally. Achenes light-brown, 4–4.5 mm, glabrous.


Phenology: Flowering Aug–Nov.
Habitat: Clayey slopes and flat, creosote bush communities
Elevation: 1000-1200 m

Discussion

Eriogonum terrenatum is confined to two geographically separate areas. Near Vail, Pima County, it is restricted to clayey outcrops of the Pantano Formation, whereas near Fairbanks, Cochise County, it is confined to the eroded, clay slopes and flats of the Saint David Formation.

Selected References

None.

Lower Taxa

None.

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... more about "Eriogonum terrenatum"
light-brown +
included +  and exserted +
3-gonous +
usually red +  and cream or yellow +
oblong +  and ellipsoid or oval +
oblanceolate;rounded +
1mm;2mm +
James L. Reveal +
Reveal +
deciduous +  and persistent +
stipelike +
Undefined subg. Eucycla +
papillate +
awn-tipped +  and simple +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
glabrous +, floccose +  and white-tomentose +
linear-elliptic;linear-oblanceolate +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
not awn-tipped +
leaflike +  and semileaflike +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
glandular +, pubescent +  and glabrous +
triangular +  and scale-like +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
not brittle +
spreading +  and erect +
scabrellous +
ridged +, angled +  and round +
spreading +  and erect +
whorled +, opposite +  and alternate +
San Pedro River wild buckwheat +
1000-1200 m +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
unisexual +, , +  and bisexual +
not attenuate +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.45 cm4.5 mm <br />0.0045 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 +
Clayey slopes and flat, creosote bush communities +
reduced +
capitate +  and subcapitate +
dense +  and diffuse +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
cymelike +, paniclelike +, racemelike +  and spikelike +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
connate +  and free +
thinly tomentose +  and subglabrous +
campanulate +
nonmembranous +
0.25 cm2.5 mm <br />0.0025 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 +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
curved +  and straight +
erect to deflexed +
0.1 cm1 mm <br />0.001 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
cylindric +  and urceolate +
accrescent +
fleshy +, indurate +  and membranous +
with extrafloral nectaries +  and not articulate +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Flowering Aug–Nov. +
homostylous +  and 3-carpellate +
, +  and solid +
slender;stout +
persistent +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
decumbent to erect +  and prostrate +
erect +  and spreading +
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 +
chambered +  and solid +
slender +  and stout +
Eriogonum terrenatum +
Eriogonum subg. Eucycla +
species +
emarginate +  and entire +
in proximal 1/2 +  and connate +
0 +  and 1/2 +
lobed +  and laciniate +
coriaceous +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
persistent +
membranous +
pubescent +  and glabrous +
floccose +  and subglabrous +
synoecious +, monocarpic +, polycarpic +  and , +
3 +, 2 +  and 1 +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +