Heterotheca monarchensis
Monarch goldenaster, Monarch Goldenaster
Family: Asteraceae · Type: Herb · Native
Conservation status: CNPS 1B.1
Heterotheca monarchensis (Monarch goldenaster) is a native California herb in the Asteraceae family, recognized by limestone habitat, small size, few heads, and long rays.
Monarch goldenaster is a rare (CNPS 1B.1) California native perennial found in southern Sierra Nevada, specifically in the Kings River canyon, growing on limestone in cracks, ledges, and flats at elevations of 1,000 to 1,900 meters. Flowering from June to October, this plant produces yellow ray flowers 10 to 15 millimeters long with bright yellow disk centers, forming small clusters of 1 to 5 flower heads. Growing 9 to 18 centimeters tall with ascending to erect stems that are densely bristly and sparsely glandular, it has a compact, clustered appearance. Its leaves are distinctive, with lower leaves oblanceolate to obovate, petioled, and wavy, while upper leaves are narrowly oblanceolate and only slightly reduced, all leaves covered in dense appressed hairs. The fruit is 2 to 3.5 millimeters long, with similar characteristics between ray and disk fruits.
Identification and appearance
Key characters: 8 sympatric species; distinguished by limestone habitat, small size, few heads, and long rays
Habitat and range
Habitat: Cracks, ledges, flats, on limestone
Elevation: 1000-1900 m
California counties: Fresno
Bloom period
Heterotheca monarchensis blooms Jun-Oct.
Conservation status
CNPS 1B.1
How to tell it apart
vs Grindelia: Heterotheca has multi-layered bracts; Grindelia bracts curve backward and flower buds are sticky-resinous.; vs Isocoma: Heterotheca has conspicuous yellow ray petals; Isocoma has only disk flowers (no rays).; vs Erigeron: Heterotheca rays are yellow and 3-12mm; Erigeron rays are white/purple/pink and typically numerous.; vs Laennecia: Heterotheca has showy 3-12mm yellow rays; Laennecia has tiny inconspicuous white rays.; vs Verbascum: Heterotheca has composite flower heads with bracts; Verbascum has simple 5-petaled flowers on tall spikes.
Frequently asked questions
Is Heterotheca monarchensis native to California?
Yes. Heterotheca monarchensis is native to California (recorded as native).
When does Heterotheca monarchensis bloom?
Heterotheca monarchensis blooms Jun-Oct.
Where in California does Heterotheca monarchensis grow?
Heterotheca monarchensis occurs in Fresno, at elevations of 1000-1900 m.
What plant family does Heterotheca monarchensis belong to?
Heterotheca monarchensis is in the Asteraceae family, genus Heterotheca.
Is Heterotheca monarchensis rare or endangered?
Heterotheca monarchensis carries California Rare Plant Rank 1B.1, state rank S2.
Related species
Other California species in the same genus, family, or bioregion.
- Heterotheca oregona — Rayless goldenaster
- Heterotheca oregona var. compacta — Compact oregon goldenaster
- Heterotheca oregona var. oregona — Oregon false goldenaster
- Heterotheca oregona var. rudis — Oregon false goldenaster
- Heterotheca oregona var. scaberrima — Oregon false goldenaster
- Heterotheca sessiliflora — Sessileflower goldenaster
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.