Agoseris grandiflora var. leptophylla
Giant mountain dandelion
(c) Hydrocycler (Elizabeth Dougherty), some rights reserved (CC BY), uploaded by Hydrocycler (Elizabeth Dougherty) · licence
Family: Asteraceae · Type: Perennial · Native
Agoseris grandiflora var. leptophylla (Giant mountain dandelion) is a native California perennial in the Asteraceae family, recognized by very narrow leaves diagnostic.
Giant mountain dandelion is a California native perennial found in northwestern California's Klamath Ranges in coastal prairie, grassland, meadows, and forest at elevations of 100 to 1,500 meters. Flowering from May to June, this plant produces yellow flowers with rosy-purple and purple-spotted involucre heads 2 to 4 centimeters long. Growing with slender stems 30 to 60 centimeters tall, it develops a delicate, elongated form. Its leaves are distinctively narrow, 2 to 4 millimeters wide, linear to linear-oblanceolate with thread-like or lance-linear lobes that taper elegantly. The plant's intricate, thread-like leaf structure and rosy-purple involucre make it a unique grassland wildflower.
Identification and appearance
Key characters: Co-occurs with 11 species; very narrow leaves diagnostic
Habitat and range
Habitat: Coastal prairie, grassland, meadows, forest
Elevation: generally 100-1500 m
California counties: Humboldt, Trinity, Del Norte, Mendocino, Napa, Butte, Lake, Siskiyou
Outside California: to British Columbia, also in Idaho
Bloom period
Agoseris grandiflora var. leptophylla blooms Generally May-Jun.
How to tell it apart
vs Taraxacum: Agoseris bracts graduate gradually in size; Taraxacum has dramatically smaller outer bracts and longer one-sided pappus.; vs Hypochaeris: Agoseris has completely bractless stems; Hypochaeris often has small leafy bracts partway up the stem.; vs Microseris: Agoseris pappus bristles evenly distributed; Microseris has 5-80 white scales (not plume-like bristles).; vs Uropappus: Agoseris has plume-like bristles; Uropappus has 5 large silvery scales alternating with 5 smaller ones.; vs Leontodon: Agoseris has unbranched scapes; Leontodon often has branched stems with multiple heads.
Frequently asked questions
Is Agoseris grandiflora var. leptophylla native to California?
Yes. Agoseris grandiflora var. leptophylla is native to California (recorded as native).
When does Agoseris grandiflora var. leptophylla bloom?
Agoseris grandiflora var. leptophylla blooms Generally May-Jun.
Where in California does Agoseris grandiflora var. leptophylla grow?
Agoseris grandiflora var. leptophylla occurs in Humboldt, Trinity, Del Norte, Mendocino, Napa, Butte, Lake, Siskiyou, at elevations of generally 100-1500 m.
What plant family does Agoseris grandiflora var. leptophylla belong to?
Agoseris grandiflora var. leptophylla is in the Asteraceae family, genus Agoseris.
What habitat does Agoseris grandiflora var. leptophylla grow in?
Agoseris grandiflora var. leptophylla grows in Coastal prairie, grassland, meadows, forest.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-09-30
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.