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

Delphinium trolliifolium

Columbian larkspur, cow-poison, poison delphinium, poison larkspur

Stems

10-40(-70) cm;

base often reddish, glabrous to puberulent.

(40-)60-120(-180) cm;

base usually reddish, glabrous to 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 ± pentagonal, 4-8 × 7-16 cm, margins ± incised, nearly glabrous; ultimate lobes 0-9, width 15-30 mm (basal), 5-20 mm (cauline), widest at middle or in proximal 1/2.

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-)14-40(-75)-flowered, ± open, at least 2 times longer than wide;

pedicel 1-4(-9) cm, puberulent to glabrous;

bracteoles (2-)6-12 mm from flowers, green, linear, 5-9(-14) 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, glabrous, lateral sepals spreading, (8-)14-21 × 5-9 mm, spurs straight or downcurved at apex, within 20° of horizontal, (10-)16-23 mm;

lower petal blades covering stamens, 5-10 mm, clefts 1.5-3 mm;

hairs sparse, mostly near junction of blade and claw, centered or on inner lobes, well dispersed, yellow.

Fruits

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

(15-)23-34 mm, 3.8-5.5 times longer than wide, glabrous.

Seeds

often winged;

seed coat cells with surfaces ± smooth.

unwinged;

seed coats smooth.

2n

= 16.

Delphinium bicolor

Delphinium trolliifolium

Phenology Flowering spring.
Habitat Oak woods, coastal chaparral, wet woodlands
Elevation 30-1100 m (100-3600 ft)
Distribution
from FNA
ID; MT; ND; NE; SD; WY; AB; BC; SK
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; OR
[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.)

Delphinium trolliifolium occurs in the northern Coast Range of California, the Columbia River Valley to just east of Mt. Hood, and the Willamette Valley of Oregon upstream to Lane County. California plants differ somewhat from Oregon plants in pubescence patterns and habitat preferences. Further study may show that two entities are involved here.

Hybrids between Delphinium trolliifolium and D. decorum, D. menziesii subsp. pallidum (D. ×pavonaceum Ewan, Peacock larkspur), D. nudicaule, D. nuttallianum, and D. nuttallii are known. Delphinium trolliifolium is likely to be confused only with D. bakeri. Refer to discussion under that species for differences.

(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
Source FNA vol. 3. FNA vol. 3.
Parent taxa Ranunculaceae > Delphinium > sect. Diedropetala > subsect. Bicoloria Ranunculaceae > Delphinium > sect. Diedropetala > subsect. Grumosa
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. 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. uliginosum, D. umbraculorum, D. variegatum, D. viridescens, D. wootonii, D. xantholeucum
Subordinate taxa
D. bicolor subsp. bicolor, D. bicolor subsp. calcicola
Name authority Nuttall: J. Acad. Nat. Sci. Philadelphia 7: 10. (1834) A. Gray: Proc. Amer. Acad. Arts 8: 375. (1872)
Web links