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Delphinium trolliifolium

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

foothill larkspur, western larkspur

Stems

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

base usually reddish, glabrous to puberulent.

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

base usually reddish, longitudinally ridged, puberulent.

Leaves

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.

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

(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.

(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, 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.

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

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

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

Seeds

unwinged;

seed coats smooth.

not echinate, appearing ± smooth to naked eye;

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

2n

= 16.

Delphinium trolliifolium

Delphinium hesperium

Phenology Flowering spring.
Habitat Oak woods, coastal chaparral, wet woodlands
Elevation 30-1100 m [100-3600 ft]
Distribution
from FNA
CA; OR
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
Discussion

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.)

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. 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. Treatment author: Michael J. Warnock. FNA vol. 3. Treatment author: Michael J. Warnock.
Parent taxa Ranunculaceae > Delphinium > sect. Diedropetala > subsect. Grumosa 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. 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
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. hesperium subsp. cuyamacae, D. hesperium subsp. hesperium, D. hesperium subsp. pallescens
Name authority A. Gray: Proc. Amer. Acad. Arts 8: 375. (1872) A. Gray: Bot. Gaz. 12: 53. (1887)
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