The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Flathead larkspur, little larkspur, low larkspur, Montana larkspur

foothill larkspur, western larkspur

Stems

10-40(-70) cm;

base often reddish, glabrous to puberulent.

(11-)40-80(-120) cm;

base usually reddish, longitudinally ridged, puberulent.

Leaves

blade round, 1-4 × 1.5-7 cm, glabrous to puberulent; ultimate lobes 3-19, width 1-8 mm (basal), 1-3 mm (cauline).

blade round to pentagonal, 1-4 × 2-6 cm, usually puberulent, especially abaxially; ultimate lobes 3-14, width 3-8 mm (basal), 2-5 mm (cauline).

Inflorescences

3-12(-22)-flowered;

pedicel 1-4(-8) cm, ± puberulent;

bracteoles 2-7(-17) mm from flowers, green, sometimes white-margined, lanceolate, 4-6(-8) mm, puberulent.

(5-)15-30(-100)-flowered, moderately open;

pedicel (0.5-)1-2.5(-7.5) cm, puberulent;

bracteoles 2-6(-12) mm from flowers, green to blue, margins often white, linear-lanceolate, 3-7(-12) mm, puberulent.

Flowers

sepals dark blue, puberulent, lateral sepals usually spreading, 16-21 × 6-12 mm, spurs straight to gently decurved, ascending 0-40° above horizontal, 13-23 mm;

lower petal blades covering stamens, 7-12 mm, clefts 0.1-3 mm;

hairs sparse, short, mostly on inner lobes below junction of blade and claw, white or yellow.

sepals dark blue to white, puberulent, lateral sepals spreading, 7-13(-16) × 3-10 mm, spurs straight to upcurved, ascending 30-45° above horizontal, 9-18 mm;

lower petal blades slightly elevated, ± exposing stamens, 3-8 mm, clefts 1-5 mm;

hairs centered, denser on inner lobes near base of cleft, white.

Fruits

(12-)16-22 mm, 4-4.5 times longer than wide, usually puberulent.

8-18 mm, 2.2-3(-4.2) times longer than wide, sparse puberulent.

Seeds

often winged;

seed coat cells with surfaces ± smooth.

not echinate, appearing ± smooth to naked eye;

seed coat cells with margins straight, surfaces smooth or roughened.

Delphinium bicolor

Delphinium hesperium

Distribution
from FNA
ID; MT; ND; NE; SD; WY; AB; BC; SK
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
Discussion

Subspecies 2 (2 in the flora).

Delphinium bicolor is closely related to D. glareosum; it differs in its wider-lobed cauline leaves, shallower petal clefts, and narrower fruits.

The Gosiute consider this plant to be poisonous (D. E. Moerman 1986, subspecies not specified).

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

Subspecies 3 (3 in the flora).

Delphinium hesperium is thought to be poisonous to cattle (D. E. Moerman 1986, no subspecies specified). It is often confused with D. hansenii. See discussion under that species for distinguishing features.

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

Key
1. Sepals (especially in fresh material) dark blue to purple; cleft in lower petals 2 mm or less; soils not derived from limestone.
subsp. bicolor
1. Sepals (especially in fresh material) bright dark blue; cleft in lower petals at least 2 mm; soils derived from limestone.
subsp. calcicola
1. Lateral sepals 4(–5) mm wide or less; inflorescence dense (individual flowers often touching in pressed specimens).
subsp. cuyamacae
1. Lateral sepals more than 4 mm wide; inflorescence open (individual flowers seldom touching in pressed specimens).
→ 2
2. Sepals dark blue-purple.
subsp. hesperium
2. Sepals white to pinkish, rarely light blue.
subsp. pallescens
Source FNA vol. 3. FNA vol. 3.
Parent taxa Ranunculaceae > Delphinium > sect. Diedropetala > subsect. Bicoloria Ranunculaceae > Delphinium > sect. Diedropetala > subsect. Echinata
Sibling taxa
D. alabamicum, D. alpestre, D. andersonii, D. andesicola, D. antoninum, D. bakeri, D. barbeyi, D. basalticum, D. brachycentrum, D. californicum, D. cardinale, D. carolinianum, D. decorum, D. depauperatum, D. distichum, D. elatum, D. exaltatum, D. geraniifolium, D. geyeri, D. glareosum, D. glaucescens, D. glaucum, D. gracilentum, D. gypsophilum, D. hansenii, D. hesperium, D. hutchinsoniae, D. inopinum, D. lineapetalum, D. luteum, D. madrense, D. menziesii, D. multiplex, D. newtonianum, D. novomexicanum, D. nudicaule, D. nuttallianum, D. nuttallii, D. parishii, D. parryi, D. patens, D. polycladon, D. purpusii, D. ramosum, D. recurvatum, D. robustum, D. sapellonis, D. scaposum, D. scopulorum, D. stachydeum, D. sutherlandii, D. treleasei, D. tricorne, D. trolliifolium, D. uliginosum, D. umbraculorum, D. variegatum, D. viridescens, D. wootonii, D. xantholeucum
D. alabamicum, D. alpestre, D. andersonii, D. andesicola, D. antoninum, D. bakeri, D. barbeyi, D. basalticum, D. bicolor, D. brachycentrum, D. californicum, D. cardinale, D. carolinianum, D. decorum, D. depauperatum, D. distichum, D. elatum, D. exaltatum, D. geraniifolium, D. geyeri, D. glareosum, D. glaucescens, D. glaucum, D. gracilentum, D. gypsophilum, D. hansenii, D. hutchinsoniae, D. inopinum, D. lineapetalum, D. luteum, D. madrense, D. menziesii, D. multiplex, D. newtonianum, D. novomexicanum, D. nudicaule, D. nuttallianum, D. nuttallii, D. parishii, D. parryi, D. patens, D. polycladon, D. purpusii, D. ramosum, D. recurvatum, D. robustum, D. sapellonis, D. scaposum, D. scopulorum, D. stachydeum, D. sutherlandii, D. treleasei, D. tricorne, D. trolliifolium, D. uliginosum, D. umbraculorum, D. variegatum, D. viridescens, D. wootonii, D. xantholeucum
Subordinate taxa
D. bicolor subsp. bicolor, D. bicolor subsp. calcicola
D. hesperium subsp. cuyamacae, D. hesperium subsp. hesperium, D. hesperium subsp. pallescens
Name authority Nuttall: J. Acad. Nat. Sci. Philadelphia 7: 10. (1834) A. Gray: Bot. Gaz. 12: 53. (1887)
Web links