Burke: Delphinium nuttallianum vs. Delphinium trolliifolium

	Delphinium nuttallianum	Delphinium trolliifolium
	thin-petal larkspur, upland larkspur	cow-poison, poison larkspur
Habit	Pubescent perennial from fleshy roots, the stems 1.5-4 dm. tall, usually single and simple.	Stout perennial from short, thick rhizomes, the several erect stems 7-15 dm. tall, simple below the inflorescence, hollow, glabrous to sparsely hairy.
Leaves	Leaves few, long-petiolate, mostly basal, the blades 2-6 cm. broad, 2-4 times parted or lobed into linear or oblong-lanceolate segments 1.5-5 mm. broad; cauline leaves much reduced upward.	Leaves numerous, evenly spaced and gradually reduced upward, the blades of the lower ones 10-20 cm. broad, tri-lobed nearly to the base, the 2 lateral lobes deeply divided into 2-3 segments, the segments broadly wedge-shaped and 2-3 times deeply toothed.
Flowers	Inflorescence simple or compound, the racemes 3-15 flowered; the lower pedicels several times as long as the flowers, spreading or ascending; sepals 5, deep purplish-blue, widely spreading, 17-25 mm. long, the lower pair the largest; the spur 13-20 mm. long, from about as long to twice as long as the top sepal; petals 4, small, the lower pair sometimes brownish or yellow-purplish, or all deep purplish-blue, the blade 3-4 mm. long, deeply bi-lobed; stamens numerous; pistils 3.	Inflorescence elongate and loose, the raceme usually simple, pubescent with spreading, yellowish hairs, leafy-bracteate below; pedicels considerably exceeding the sepal spur, spreading; sepals 5, deep blue, oblong-lanceolate and pointed, 18-25 mm. long, the spur straight, about equal to the blade of the upper sepal; petals 4, small, the lower pair colored as the sepals, the upper pair white; stamens numerous; pistils 3.
Fruits	Follicles 15-22 mm. long, somewhat spreading.	Follicles glabrous, about 15 mm. long.
Comments	Specimen records from west of the Cascade Mountains need to be re-examined.

	Delphinium nuttallianum	Delphinium trolliifolium
Flowering time	March-August	April-May
Habitat	Dry, gravelly ground, sagebrush deserts to the ponderosa pine region in the mountains.	Moist, shady woods at low to middle elevations.
Distribution	Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains. [WildflowerSearch map] [BONAP county map]	Occurring west of the Cascades crest and in the Columbia River Gorge in Washington; Washington south to California. [WildflowerSearch map] [BONAP county map]
Origin	Native	Native
Conservation status	Not of concern	Not of concern
Sibling taxa	D. ajacis, D. basalticum, D. ×burkei, D. depauperatum, D. distichum, D. glareosum, D. glaucum, D. leucophaeum, D. lineapetalum, D. menziesii, D. multiplex, D. nuttallii, D. occidentale, D. stachydeum, D. sutherlandii, D. trolliifolium, D. viridescens, D. xantholeucum	D. ajacis, D. basalticum, D. ×burkei, D. depauperatum, D. distichum, D. glareosum, D. glaucum, D. leucophaeum, D. lineapetalum, D. menziesii, D. multiplex, D. nuttallianum, D. nuttallii, D. occidentale, D. stachydeum, D. sutherlandii, D. viridescens, D. xantholeucum
Web links	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria, Turner Photog. WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria, Turner Photog. WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Delphinium trolliifolium

thin-petal larkspur, upland larkspur

cow-poison, poison larkspur

Habit

Pubescent perennial from fleshy roots, the stems 1.5-4 dm. tall, usually single and simple.

Stout perennial from short, thick rhizomes, the several erect stems 7-15 dm. tall, simple below the inflorescence, hollow, glabrous to sparsely hairy.

Leaves

Leaves few, long-petiolate, mostly basal, the blades 2-6 cm. broad, 2-4 times parted or lobed into linear or oblong-lanceolate segments 1.5-5 mm. broad;

cauline leaves much reduced upward.

Leaves numerous, evenly spaced and gradually reduced upward, the blades of the lower ones 10-20 cm. broad, tri-lobed nearly to the base, the 2 lateral lobes deeply divided into 2-3 segments, the segments broadly wedge-shaped and 2-3 times deeply toothed.

Flowers

Inflorescence simple or compound, the racemes 3-15 flowered; the lower pedicels several times as long as the flowers, spreading or ascending;

sepals 5, deep purplish-blue, widely spreading, 17-25 mm. long, the lower pair the largest; the spur 13-20 mm. long, from about as long to twice as long as the top sepal;

petals 4, small, the lower pair sometimes brownish or yellow-purplish, or all deep purplish-blue, the blade 3-4 mm. long, deeply bi-lobed;

stamens numerous;

pistils 3.

Inflorescence elongate and loose, the raceme usually simple, pubescent with spreading, yellowish hairs, leafy-bracteate below;

pedicels considerably exceeding the sepal spur, spreading;

sepals 5, deep blue, oblong-lanceolate and pointed, 18-25 mm. long, the spur straight, about equal to the blade of the upper sepal;

petals 4, small, the lower pair colored as the sepals, the upper pair white;

stamens numerous;

pistils 3.

Fruits

Follicles 15-22 mm. long, somewhat spreading.

Follicles glabrous, about 15 mm. long.