Calycadenia hooveri
Hoover's calycadenia
(c) Trevor Van Loon, some rights reserved (CC BY) · licence
Family: Asteraceae · Type: Herb · Native
Conservation status: CNPS 1B.3
Calycadenia hooveri (Hoover's calycadenia) is a native California herb in the Asteraceae family, recognized by . Key features: thread-like flexible branches, very small white rays 2-3.5mm, only 1-2 disk flowers.
Hoover's calycadenia is a rare (CNPS 1B.3) California native annual found in northern and central Sierra Nevada Foothill and San Joaquin Valley grasslands and oak savannas at elevations of 100 to 400 meters. Flowering from June to September, this plant produces delicate white ray flowers with asymmetric lateral lobes in small heads. Growing with slender, thread-like stems 10 to 60 centimeters tall that branch extensively and feature minute glandular surfaces, it spreads with flexible, intricately structured branches. Its proximal leaves are numerous, ranging 1 to 8 centimeters long, with thread-like branchlets that bear distinctive tack-like glands. The fruit develops with smooth or occasionally wrinkled surfaces, complemented by 6 to 13 lanceolate pappus scales.
Identification and appearance
Key characters: 4 sympatric species. Key features: thread-like flexible branches, very small white rays 2-3.5mm, only 1-2 disk flowers
Habitat and range
Habitat: Rocky, exposed places, grassland, oak savanna
Elevation: 100-400 m
Bloom period
Calycadenia hooveri blooms Jun-Sep.
Conservation status
CNPS 1B.3
How to tell it apart
vs Hemizonia: Calycadenia rays deeply fringed; Hemizonia rays shallowly lobed with ray fruits beaked.; vs Osmadenia: Calycadenia covered with tack glands; Osmadenia completely lacks sticky glands.; vs Deinandra: Calycadenia rays deeply split; Deinandra rays shallowly lobed or entire.; vs Madia: Calycadenia has tack glands and deeply split rays; Madia lacks tack glands, different ray shape.; vs Holocarpha: Calycadenia has tack glands (not pit glands); Holocarpha has pit-gland depressions on bracts.
Frequently asked questions
Is Calycadenia hooveri native to California?
Yes. Calycadenia hooveri is native to California (recorded as native).
When does Calycadenia hooveri bloom?
Calycadenia hooveri blooms Jun-Sep.
What plant family does Calycadenia hooveri belong to?
Calycadenia hooveri is in the Asteraceae family, genus Calycadenia.
Is Calycadenia hooveri rare or endangered?
Calycadenia hooveri carries California Rare Plant Rank 1B.3, state rank S2.
What habitat does Calycadenia hooveri grow in?
Calycadenia hooveri grows in Rocky, exposed places, grassland, oak savanna.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CNPS Rare Plant Inventory · Index of California Plant Names · CalPhotos · CDFW CNDDB
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.