Delphinium xantholeucum
Delphinium
yellow-white larkspur
delphinium, larkspur
40-60(-100) cm;
base often reddish, glabrous, ± glaucous.
blade round, 2-6 × 4-10 cm, nearly glabrous; ultimate lobes 3-15, width 3-8 mm (basal), 1-5 mm (cauline).
blade deeply palmately divided, round to pentagonal or reniform, margins entire or lobes apically crenate or lacerate, lobes of basal blades wider and fewer than those of cauline blades.
10-20(-60)-flowered, narrowly pyramidal;
pedicel spreading, yellowish, 1.5-3 cm, ± glandular-puberulent;
bracteoles 6-12 mm from flowers, green to light brown, linear to lanceolate, 4-7 mm, nearly glabrous.
terminal, 2-100(-more)-flowered racemes (occasionally branched, thus technically panicles), 5-40 cm or more;
bracts subtending inflorescence branches;
pedicels present or absent;
bracteoles (on pedicels) subopposite-subalternate, not forming involucre.
sepals yellow, glabrous, lateral sepals reflexed, 9-12 × 3-5 mm, spurs straight, ascending ca. 45° above horizontal, 11-15 mm;
lower petal blades elevated, exposing stamens, 3-5 mm, clefts 1-2 mm;
hairs centered mostly on inner lobes near base of cleft, white.
bisexual, bilaterally symmetric;
sepals not persistent in fruit, 5;
upper sepal 1, spurred, 8-24 mm;
lateral sepals 2, ± ovate to elliptic, 8-18 mm;
lower sepals 2, similar to lateral sepals;
upper petals 2, spurred, enclosed in upper sepal, nectary inside tip of spur;
lower petals 2, plane, ± ovate, ± 2-lobed, clawed, 2-12 mm, nectary absent;
stamens 25-40;
filaments with base expanded;
staminodes absent between stamens and pistils;
pistils 3(-5), simple;
ovules 8-20 per pistil;
style present.
15-22 mm, 3-4 times longer than wide, glabrous to glandular-puberulent.
follicles, aggregate, sessile, ± curved-cylindric, sides prominently veined or not;
beak terminal, straight, 2-4 mm.
seed coat cells narrow, short, cell margins straight, surfaces smooth.
dark brown to black (often appearing white because of air in seed coat cells), rectangular to pyramidal, often ± rough surfaced.
= 8.
= 16.
Delphinium xantholeucum
Delphinium
Of conservation concern.
Delphinium xantholeucum is very local; much of the habitat of this species has been converted to orchards.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Species ca. 300 (61 in the flora).
Three Eurasian species of Delphinium–D. elatum Linnaeus, D. grandiflorum Linnaeus, and D. tatsienense Franchet–have been commonly cultivated in North America. Of the nonnative taxa, only D. elatum is sporadically naturalized, as far as is known. Isolating mechanisms in Delphinium appear to be primarily ecological, geographic, and/or temporal. Where these distinctions are disrupted, introgression often exists. Hybridization occurs regularly between certain taxa, particularly in areas of disturbance (e.g., roadcuts, drainage ditches, clearcuts). The more common and easily recognized hybrids are included in the key.
Many names have been misapplied in Delphinium. The few misapplied names mentioned in discussions below refer to relatively widespread problems.
Unless otherwise noted, the key and descriptions refer to fresh material. Some features may be significantly altered by pressing; they can, however, usually be determined with a certain amount of effort and experience.
In the descriptions, "base of cleft" refers to the point where the cleft or sinus reaches most deeply into the petal blade.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Lower petal blades less than 1/5 length of lateral sepals; sepals never red or yellow. | Sect. Elatopsis |
1. Lower petal blades more than 1/5 length of lateral sepals; sepals blue, purple, white, red, or yellow. | Sect. Diedropetala |
WA
Flora NW
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
CA
OR
