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Shockley's buckwheat, Shockley's wild buckwheat

jointed buckwheat, napkinring, napkinring wild buckwheat

Habit Herbs, matted, scapose, 0.3–0.5(–0.7) × (0.5–)1–4(–20) dm, floccose to tomentose, greenish or grayish. Herbs, 6–15 × 0.3–0.9 dm, grayish.
Stems

matted, sometimes only seemingly so, with persistent leaf bases, up to 1/5 height of plant;

caudex stems matted;

aerial flowering stems absent or scapelike, erect or nearly so, slender, solid, not fistulose, (0.05–)0.1–0.3 dm, floccose to tomentose.

Aerial flowering stems

5–12 dm, disarticulating into ringlike segments 3–10(–16) mm.

Leaves

basal, fasciculate in terminal tufts;

petiole 0.2–0.5 cm, tomentose to floccose;

blade oblanceolate to elliptic or spatulate, (0.2–)0.3–0.8(–1.2) × 0.2–0.4(–0.6) cm, tomentose to floccose, margins plane or slightly thickened.

petiole 3–8 cm, pilose;

blade oblong-ovate, 2.5–7 × 0.7–2(–3) cm, pilose on both surfaces, margins entire.

Inflorescences

capitate, 0.8–2 cm;

branches absent;

bracts 3–5, scalelike, linear to linear-lanceolate, 1.5–4 × 0.6–1 mm.

1–3 × 2–6 cm;

bracts scalelike distally, triangular, and 1–3 mm, semileaflike proximally, oblong, and 3–6 mm.

Peduncles

absent.

Involucres

2–4(–6) per cluster, campanulate, (2–)2.5–5(–6) × 3–6(–7) mm, rigid, tomentose;

teeth 5–10, erect to spreading, (0.5–)1–3 mm.

2.5–3.5 × 3–5 mm, pilose;

teeth 0.5–2 mm.

Flowers

2.5–4 mm;

perianth white to rose or yellow, densely pilose;

tepals connate proximally, monomorphic, oblong to obovate;

stamens exserted, 2.5–5 mm;

filaments subglabrous or sparsely pilose proximally.

1.5–3 mm;

tepals: those of outer whorl oblanceolate, 0.9–1.2 mm wide, those of inner whorl broadly oblanceolate to fan-shaped, 1–1.5 mm wide;

stamens 0.8–1.5 mm.

Achenes

light brown to brown, 2.5–3 mm, tomentose.

2–2.5 mm.

2n

= 40.

Eriogonum shockleyi

Eriogonum intrafractum

Phenology Flowering May–Aug. Flowering May–Oct.
Habitat Gravelly or clayey (rarely sandy) flats, washes, and slopes, saltbush, blackbrush, and sagebrush communities, pinyon-juniper woodlands Limestone washes, slopes, and cliffs, saltbush and creosote bush communities, juniper woodlands
Elevation (800-)1200-2600 m ((2600-)3900-8500 ft) (600-)800-1600 m ((2000-)2600-5200 ft)
Distribution
from FNA
AZ; CA; CO; ID; NM; NV; UT
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[BONAP county map]
Discussion

Eriogonum shockleyi is widely distributed in northern Arizona, east-central California, western Colorado, southern Idaho, northwestern New Mexico, Nevada, and Utah. On the Colorado Plateau, it has oblanceolate to spatulate leaf blades usually 0.3–1.2 × 0.3–0.6 cm, scapes 1–3 cm, involucres with long (2–3.5 mm) often spreading teeth, and flowers 3–4 mm. These plants have been distinguished as var. longilobum. The typical Great Basin expression has elliptic leaf blades 0.3–0.6 × 0.3–0.5 cm, scapes 0.5–2 cm, involucres with short (0.5–2 mm) erect teeth, and flowers 2.5–4 mm. Low, compact, hummock-like plants in southwestern Idaho with elliptic leaf blades 0.1–0.3(–0.35) × 0.1–0.15 cm, flowering stems absent or up to 0.5 cm, and involucres 2.5–3 mm with teeth 0.8–1 mm have been termed var. packardiae. These morphologic differences have been shown to be genetically insignificant, however (J. F. Smith and T. A. Bateman 2002). Plants on moving sand dunes at the southeast end of Baking Power Flat in Lincoln County, Nevada, can be up to 2 m across. Further studies may indicate that the various geographic expressions deserve taxonomic recognition.

The Great Basin expression is the food plant of the Bernardino dotted-blue butterfly (Euphilotes bernardino). Members of the species are occasionally found in cultivation.

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

Of conservation concern.

Rare and restricted to the Cottonwood, Funeral, Grapevine, and Panamint ranges of Death Valley National Park, Inyo County, Eriogonum intrafractum is one of the more remarkable species of the genus. The tall, simple, glabrous stem is branched only near the top, and then with only two to five inflorescence branches. The small leaves are restricted to the base of the plant. The lower part of the stem, when dried, fragments into napkinring-like segments. The rings have no evident value to the species, as they are not capable of vegetative reproduction. Some parenchyma cells at the fracture points are large enough to be seen with the naked eye, and it is likely that they act as compression points. Much as the intervertebral disks in the vertebral column provide a degree of flexibility, so too may these large parenchyma cells allow the top-heavy flowering stem to move in the wind without breaking. The flowers are numerous, each involucre so filled with more than a hundred flowers that it is torn apart by late anthesis.

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

Source FNA vol. 5, p. 286. FNA vol. 5, p. 328.
Parent taxa Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Eucycla Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Clastomyelon
Sibling taxa
E. abertianum, E. acaule, E. alatum, E. aliquantum, E. allenii, E. alpinum, E. ammophilum, E. ampullaceum, E. androsaceum, E. anemophilum, E. angulosum, E. annuum, E. apiculatum, E. apricum, E. arborescens, E. arcuatum, E. aretioides, E. argillosum, E. argophyllum, E. arizonicum, E. artificis, E. atrorubens, E. baileyi, E. batemanii, E. bicolor, E. bifurcatum, E. brachyanthum, E. brachypodum, E. brandegeei, E. breedlovei, E. brevicaule, E. butterworthianum, E. caespitosum, E. capillare, E. cernuum, E. chrysops, E. cinereum, E. cithariforme, E. clavatum, E. clavellatum, E. codium, E. collinum, E. coloradense, E. compositum, E. concinnum, E. congdonii, E. contiguum, E. contortum, E. correllii, E. corymbosum, E. covilleanum, E. crocatum, E. cronquistii, E. crosbyae, E. cusickii, E. darrovii, E. dasyanthemum, E. davidsonii, E. deflexum, E. deserticola, E. desertorum, E. diatomaceum, E. diclinum, E. divaricatum, E. douglasii, E. eastwoodianum, E. effusum, E. elatum, E. elegans, E. elongatum, E. ephedroides, E. eremicola, E. eremicum, E. ericifolium, E. esmeraldense, E. evanidum, E. exaltatum, E. exilifolium, E. fasciculatum, E. flavum, E. fusiforme, E. giganteum, E. gilmanii, E. glandulosum, E. gordonii, E. gossypinum, E. gracile, E. gracilipes, E. gracillimum, E. grande, E. greggii, E. gypsophilum, E. havardii, E. heermannii, E. helichrysoides, E. hemipterum, E. heracleoides, E. hieracifolium, E. hirtellum, E. hirtiflorum, E. hoffmannii, E. holmgrenii, E. hookeri, E. howellianum, E. hylophilum, E. incanum, E. inerme, E. inflatum, E. intrafractum, E. jamesii, E. jonesii, E. kelloggii, E. kennedyi, E. kingii, E. lachnogynum, E. lancifolium, E. latens, E. latifolium, E. lemmonii, E. leptocladon, E. leptophyllum, E. libertini, E. lobbii, E. loganum, E. lonchophyllum, E. longifolium, E. luteolum, E. maculatum, E. mancum, E. marifolium, E. mensicola, E. microthecum, E. mitophyllum, E. mohavense, E. molestum, E. mortonianum, E. multiflorum, E. natum, E. nealleyi, E. nervulosum, E. nidularium, E. niveum, E. nortonii, E. novonudum, E. nudum, E. nummulare, E. nutans, E. ochrocephalum, E. ordii, E. ostlundii, E. ovalifolium, E. palmerianum, E. panamintense, E. panguicense, E. parishii, E. parvifolium, E. pauciflorum, E. pelinophilum, E. pendulum, E. pharnaceoides, E. plumatella, E. polycladon, E. polypodum, E. prattenianum, E. prociduum, E. pulchrum, E. pusillum, E. pyrolifolium, E. racemosum, E. reniforme, E. ripleyi, E. rixfordii, E. robustum, E. rosense, E. roseum, E. rotundifolium, E. rubricaule, E. rupinum, E. salicornioides, E. saxatile, E. scabrellum, E. scopulorum, E. siskiyouense, E. smithii, E. soliceps, E. soredium, E. spathulatum, E. spectabile, E. spergulinum, E. sphaerocephalum, E. strictum, E. subreniforme, E. suffruticosum, E. temblorense, E. tenellum, E. ternatum, E. terrenatum, E. thomasii, E. thompsoniae, E. thornei, E. thurberi, E. thymoides, E. tiehmii, E. tomentosum, E. trichopes, E. tripodum, E. truncatum, E. tumulosum, E. twisselmannii, E. umbellatum, E. ursinum, E. vestitum, E. villiflorum, E. vimineum, E. viridescens, E. viridulum, E. viscidulum, E. visheri, E. watsonii, E. wetherillii, E. wootonii, E. wrightii, E. zionis
E. abertianum, E. acaule, E. alatum, E. aliquantum, E. allenii, E. alpinum, E. ammophilum, E. ampullaceum, E. androsaceum, E. anemophilum, E. angulosum, E. annuum, E. apiculatum, E. apricum, E. arborescens, E. arcuatum, E. aretioides, E. argillosum, E. argophyllum, E. arizonicum, E. artificis, E. atrorubens, E. baileyi, E. batemanii, E. bicolor, E. bifurcatum, E. brachyanthum, E. brachypodum, E. brandegeei, E. breedlovei, E. brevicaule, E. butterworthianum, E. caespitosum, E. capillare, E. cernuum, E. chrysops, E. cinereum, E. cithariforme, E. clavatum, E. clavellatum, E. codium, E. collinum, E. coloradense, E. compositum, E. concinnum, E. congdonii, E. contiguum, E. contortum, E. correllii, E. corymbosum, E. covilleanum, E. crocatum, E. cronquistii, E. crosbyae, E. cusickii, E. darrovii, E. dasyanthemum, E. davidsonii, E. deflexum, E. deserticola, E. desertorum, E. diatomaceum, E. diclinum, E. divaricatum, E. douglasii, E. eastwoodianum, E. effusum, E. elatum, E. elegans, E. elongatum, E. ephedroides, E. eremicola, E. eremicum, E. ericifolium, E. esmeraldense, E. evanidum, E. exaltatum, E. exilifolium, E. fasciculatum, E. flavum, E. fusiforme, E. giganteum, E. gilmanii, E. glandulosum, E. gordonii, E. gossypinum, E. gracile, E. gracilipes, E. gracillimum, E. grande, E. greggii, E. gypsophilum, E. havardii, E. heermannii, E. helichrysoides, E. hemipterum, E. heracleoides, E. hieracifolium, E. hirtellum, E. hirtiflorum, E. hoffmannii, E. holmgrenii, E. hookeri, E. howellianum, E. hylophilum, E. incanum, E. inerme, E. inflatum, E. jamesii, E. jonesii, E. kelloggii, E. kennedyi, E. kingii, E. lachnogynum, E. lancifolium, E. latens, E. latifolium, E. lemmonii, E. leptocladon, E. leptophyllum, E. libertini, E. lobbii, E. loganum, E. lonchophyllum, E. longifolium, E. luteolum, E. maculatum, E. mancum, E. marifolium, E. mensicola, E. microthecum, E. mitophyllum, E. mohavense, E. molestum, E. mortonianum, E. multiflorum, E. natum, E. nealleyi, E. nervulosum, E. nidularium, E. niveum, E. nortonii, E. novonudum, E. nudum, E. nummulare, E. nutans, E. ochrocephalum, E. ordii, E. ostlundii, E. ovalifolium, E. palmerianum, E. panamintense, E. panguicense, E. parishii, E. parvifolium, E. pauciflorum, E. pelinophilum, E. pendulum, E. pharnaceoides, E. plumatella, E. polycladon, E. polypodum, E. prattenianum, E. prociduum, E. pulchrum, E. pusillum, E. pyrolifolium, E. racemosum, E. reniforme, E. ripleyi, E. rixfordii, E. robustum, E. rosense, E. roseum, E. rotundifolium, E. rubricaule, E. rupinum, E. salicornioides, E. saxatile, E. scabrellum, E. scopulorum, E. shockleyi, E. siskiyouense, E. smithii, E. soliceps, E. soredium, E. spathulatum, E. spectabile, E. spergulinum, E. sphaerocephalum, E. strictum, E. subreniforme, E. suffruticosum, E. temblorense, E. tenellum, E. ternatum, E. terrenatum, E. thomasii, E. thompsoniae, E. thornei, E. thurberi, E. thymoides, E. tiehmii, E. tomentosum, E. trichopes, E. tripodum, E. truncatum, E. tumulosum, E. twisselmannii, E. umbellatum, E. ursinum, E. vestitum, E. villiflorum, E. vimineum, E. viridescens, E. viridulum, E. viscidulum, E. visheri, E. watsonii, E. wetherillii, E. wootonii, E. wrightii, E. zionis
Synonyms E. pulvinatum, E. shockleyi subsp. candidum, E. shockleyi subsp. longilobum, E. shockleyi var. longilobum, E. shockleyi var. packardiae, E. villiflorum var. candidum
Name authority S. Watson: Proc. Amer. Acad. Arts 18: 194. (1883) Coville & C. V. Morton: J. Wash. Acad. Sci. 26: 305. (1936)
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