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Robinson's onion

plains onion

Bulbs

1–3+, not clustered on stout primary rhizome, rhizomes absent, renewal bulbs formed within coats of parent bulb, increase bulbs absent or 1–2, ± equaling parent bulbs, never appearing as basal cluster, ovoid, 1–2 cm × 8–15 mm;

outer coats grayish to brownish, membranous, lacking cellular reticulation or cells arranged in only 2–3 rows distal to roots, ± quadrate, without fibers;

inner coats white, cells absent or ± quadrate.

2–20+, without basal bulbels, 1–2.5 × 1.2–2.8 cm;

outer coats enclosing 1 or more bulbs, dark brown, reticulate, cells coarse-meshed, open, fibrous;

inner coats whitish, cells regular, vertically elongate, walls not sinuous.

Leaves

usually deciduous with scape, 2, basally sheathing, sheaths not extending much above soil surface;

blade solid, flat, strongly falcate, 5–18 cm × 1–2 mm, margins entire.

persistent, green at anthesis, 3–5, sheathing;

blade solid, flat, channeled, 8–30 cm × 1–2(–3) mm, margins entire.

Scape

usually forming abcission layer and deciduous with leaves after seeds mature, frequently breaking at this level after pressing, solitary, erect, solid, flattened, slightly 2-edged, 3–7 cm × 1–3 mm.

persistent, solitary, erect, ± terete, 10–20 cm × 1–3 mm.

Umbel

deciduous with scape, erect, compact, 5–12-flowered, hemispheric, bulbils unknown;

spathe bracts persistent, 2, 5–8-veined, ovate, ± equal, apex abruptly acute.

persistent, erect, loose, 5–25-flowered, hemispheric-globose, bulbils unknown;

spathe bracts persistent, 2–3, 3–7-veined, ovate, ± equal, apex acuminate.

Flowers

campanulate, 7–9 mm;

tepals erect, white to pale pink with red midribs, oblong, ± equal, becoming papery and not carinate in fruit, margins entire, apex obtuse;

stamens included;

anthers purple;

pollen gray or yellow;

ovary ± distinctly crested;

processes 3 or 6, central, low, rounded, margins entire;

style included, linear;

stigma capitate, unlobed;

pedicel 3–12 mm.

urceolate, 7–10 mm;

tepals erect, white or pale pink with deep pink midribs to deep rose, lanceolate, ± equal, becoming callous-keeled and permanently investing capsule, margins entire, apex obtuse or acute;

stamens included;

anthers yellow or purple;

pollen yellow;

ovary crestless;

style linear, ± equaling stamens;

stigma capitate, unlobed or obscurely lobed;

pedicel 3–17 mm, ± 2 times perianth at anthesis, elongating in fruit.

Seed

coat dull;

cells smooth.

coat dull or shining;

cells minutely roughened.

2n

= 14.

Allium robinsonii

Allium perdulce

Phenology Flowering Apr–May.
Habitat Sand and gravel deposits along bottom and lower benches of Columbia River
Elevation 50–200 m (200–700 ft)
Distribution
from FNA
OR; WA
[WildflowerSearch map]
[BONAP county map]
from USDA
c North America
[WildflowerSearch map]
[BONAP county map]
Discussion

Allium robinsonii has been found along the Columbia River from Ferry County, northeastern Washington, to about the mouth of the John Day River, north-central Oregon, and is now possibly extirpated from Oregon.

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

Varieties 2 (2 in the flora).

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

Key
1. Tepals deep rose, aging to purple; n Texas and e New Mexico to se South Dakota and adjacent Iowa
var. perdulce
1. Tepals white to light pink, aging pink; trans-Pecos Texas.
var. sperryi
Source FNA vol. 26, p. 276. FNA vol. 26, p. 241.
Parent taxa Liliaceae > Allium Liliaceae > Allium
Sibling taxa
A. aaseae, A. abramsii, A. acuminatum, A. ampeloprasum, A. amplectens, A. anceps, A. atrorubens, A. bigelovii, A. bisceptrum, A. bolanderi, A. brandegeei, A. brevistylum, A. burlewii, A. campanulatum, A. canadense, A. cepa, A. cernuum, A. columbianum, A. constrictum, A. coryi, A. cratericola, A. crenulatum, A. crispum, A. cuthbertii, A. denticulatum, A. diabolense, A. dichlamydeum, A. dictuon, A. douglasii, A. drummondii, A. elmendorfii, A. falcifolium, A. fibrillum, A. fimbriatum, A. fistulosum, A. geyeri, A. gooddingii, A. haematochiton, A. hickmanii, A. hoffmanii, A. howellii, A. hyalinum, A. jepsonii, A. kunthii, A. lacunosum, A. lemmonii, A. macropetalum, A. macrum, A. madidum, A. membranaceum, A. monticola, A. munzii, A. neapolitanum, A. nevadense, A. nevii, A. nigrum, A. obtusum, A. oleraceum, A. paniculatum, A. parishii, A. parryi, A. parvum, A. passeyi, A. peninsulare, A. perdulce, A. platycaule, A. plummerae, A. praecox, A. punctum, A. rhizomatum, A. rotundum, A. runyonii, A. sanbornii, A. sativum, A. schoenoprasum, A. scilloides, A. serra, A. sharsmithiae, A. shevockii, A. simillimum, A. siskiyouense, A. speculae, A. stellatum, A. textile, A. tolmiei, A. tribracteatum, A. tricoccum, A. triquetrum, A. tuberosum, A. tuolumnense, A. unifolium, A. validum, A. victorialis, A. vineale, A. yosemitense
A. aaseae, A. abramsii, A. acuminatum, A. ampeloprasum, A. amplectens, A. anceps, A. atrorubens, A. bigelovii, A. bisceptrum, A. bolanderi, A. brandegeei, A. brevistylum, A. burlewii, A. campanulatum, A. canadense, A. cepa, A. cernuum, A. columbianum, A. constrictum, A. coryi, A. cratericola, A. crenulatum, A. crispum, A. cuthbertii, A. denticulatum, A. diabolense, A. dichlamydeum, A. dictuon, A. douglasii, A. drummondii, A. elmendorfii, A. falcifolium, A. fibrillum, A. fimbriatum, A. fistulosum, A. geyeri, A. gooddingii, A. haematochiton, A. hickmanii, A. hoffmanii, A. howellii, A. hyalinum, A. jepsonii, A. kunthii, A. lacunosum, A. lemmonii, A. macropetalum, A. macrum, A. madidum, A. membranaceum, A. monticola, A. munzii, A. neapolitanum, A. nevadense, A. nevii, A. nigrum, A. obtusum, A. oleraceum, A. paniculatum, A. parishii, A. parryi, A. parvum, A. passeyi, A. peninsulare, A. platycaule, A. plummerae, A. praecox, A. punctum, A. rhizomatum, A. robinsonii, A. rotundum, A. runyonii, A. sanbornii, A. sativum, A. schoenoprasum, A. scilloides, A. serra, A. sharsmithiae, A. shevockii, A. simillimum, A. siskiyouense, A. speculae, A. stellatum, A. textile, A. tolmiei, A. tribracteatum, A. tricoccum, A. triquetrum, A. tuberosum, A. tuolumnense, A. unifolium, A. validum, A. victorialis, A. vineale, A. yosemitense
Subordinate taxa
A. perdulce var. perdulce, A. perdulce var. sperryi
Name authority L. F. Henderson: Rhodora 32: 22. (1930) S. V. Fraser: Trans. Kansas Acad. Sci. 42: 124. (1940)
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