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angle stem buckwheat, angle-stem wild buckwheat

Siskiyou buckwheat, Siskiyou wild buckwheat

Habit Herbs, erect to spreading, annual, 1–5(–10) dm, tomen-tose to floccose or glabrous, usually grayish. Herbs, spreading, matted, 0.5–2 × 1–5 dm, glabrate or glabrous.
Stems

caudex absent;

aerial flowering stems erect, striated, angled, solid, not fistulose, 0.5–1 dm, tomentose to floccose.

caudex spreading;

aerial flowering stems erect, slender, solid, not fistulose, arising at nodes of caudex branches and at distal nodes of short, non-flowering aerial branches, 0.5–1.5(–2) dm, usually glabrous, with a whorl of 2–4 leaflike bracts ca. midlength, similar to leaf blade, 0.3–0.5 × 0.1–0.2 cm.

Leaves

basal and cauline;

basal: petiole 0.5–3 cm, mostly floccose, blade oblanceolate to oblong-lanceolate, 1–4(–4.5) × (0.2–)0.5–1(–1.3) cm, tomentose abaxially, floccose or glabrate and grayish or greenish adaxially, margins crenulate;

cauline sessile, blade lanceolate to oblong, 0.5–2 × 0.3–0.8 cm, similar to basal blade.

in dense compact basal rosettes;

petiole 0.2–0.6 cm, glabrate or glabrous;

blade spatulate to round, (0.3–)0.5–0.8 × (0.2–)0.3–0.5(–0.7) cm, densely white to thinly tomentose abaxially, sparsely floccose to glabrate and green or olive green adaxially, rarely glabrous on both surfaces, margins entire, plane.

Inflorescences

cymose, open, 5–80 × 10–60 cm;

branches striated, angled, sparsely tomentose to glabrate;

bracts 3, scalelike, 1–3 × 1–3 mm.

capitate, rarely umbellate, 0.8–1.5 cm wide or 1–2 × 1–3 cm;

branches usually glabrate;

bracts absent immediately below involucre.

Peduncles

erect, straight, slender, 1–2 cm, sparsely tomentose to glabrous.

Involucres

turbinate-campanulate to campanulate, 1.5–2.5(–3) × 1.5–2.5(–3), sparsely puberulent;

teeth 5, erect, 0.3–0.6 mm.

1 per node, turbinate-campanulate to campanulate, (3–)3.5–4 × 4–6 mm, arachnoid-tomentose;

teeth 6–10, lobelike, reflexed, (2–)2.5–3.5 mm.

Flowers

1.5–1.8 mm;

perianth white to rose, without a conspicuous rose-purple spot on each outer tepal, minutely glandular-puberulent;

tepals dimorphic, those of outer whorl elliptic to obovate, sometimes inflated proximally, those of inner whorl narrowly spatulate;

stamens exserted, 2–3 mm;

filaments pilose proximally.

(4–)4.5–6 mm, including 0.6–1 mm stipelike base;

perianth sulphur yellow, glabrous;

tepals monomorphic, oblong;

stamens exserted, 3.5–5 mm;

filaments pilose proximally.

Achenes

light brown to brown, 3-gonous, 1–1.5 mm, glabrous.

light brown, 4.5–5 mm, glabrous.

Eriogonum angulosum

Eriogonum siskiyouense

Phenology Flowering year-round. Flowering Jul–Sep.
Habitat Clayey flats and slopes, mixed grassland, saltbush, and chaparral communities, oak and conifer woodlands Gravelly serpentine slopes and outcrops, manzanita communities, montane conifer woodlands
Elevation 0-800 m (0-2600 ft) 1600-2800 m (5200-9200 ft)
Distribution
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[BONAP county map]
Discussion

The name Eriogonum angulosum has been applied to all of the members of its species complex except E. gossypinum. Since the 1950s, the name consistently has been applied to plants with long, exserted stamens and strongly angled stems of the Inner Coast Ranges (Alameda and Contra Costa counties south), the western foothills of the southern Sierra Nevada (Tulare County south), and the Central Valley (San Joaquin County south). The southern edge of the range is the northern foothills of the Transverse Ranges (Ventura and Los Angeles counties). The species can be common and occasionally abundant but rarely is weedy. A mixed collection (with E. gracillimum) from Barstow, San Bernardino County (K. Brandegee s.n., May 1913, UC), and two sheets of the species from San Diego gathered by Susan Stokes apparently in 1895 (B, SD) are discounted as to location.

In late fruit, the bractlets at the base of the pedicel inside the involucres of Eriogonum angulosum often elongate and broaden into oblanceolate segments that fill the involucre. As a result, the involucre appears to have several rows of teeth. This feature may be seen also in E. viridescens, but typically the involucres there appear to have only two or three rows of teeth. This feature is seen rarely in E. maculatum.

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

Eriogonum siskiyouense is restricted to the ridge system that extends from the Scott Mountain area to the Mt. Eddy region of Siskiyou and Trinity counties. The vast majority of individuals in a population have a single involucre atop each flowering stem, but at lower elevations and in somewhat more protected sites the inflorescence may be umbellate. The Siskiyou wild buckwheat does well in cultivation if its soil requirements are fulfilled.

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

Source FNA vol. 5, p. 411. FNA vol. 5, p. 356.
Parent taxa Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Ganysma Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Oligogonum
Sibling taxa
E. abertianum, E. acaule, E. alatum, E. aliquantum, E. allenii, E. alpinum, E. ammophilum, E. ampullaceum, E. androsaceum, E. anemophilum, 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. 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
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. shockleyi, 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. ursinum var. siskiyouense
Name authority Bentham: Trans. Linn. Soc. London 17: 406, plate 18, fig. 1. (1836) Small: Bull. Torrey Bot. Club 25: 44. (1898)
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