Symphyotrichum lentum
Suisun marsh aster
(c) Ken-ichi Ueda, some rights reserved (CC BY) · licence
Family: Asteraceae · Type: Herb · Native
Conservation status: CNPS 1B.2
Symphyotrichum lentum (Suisun marsh aster) is a native California herb in the Asteraceae family, recognized by marsh habitat and smooth tall stems with narrow leaves.
Suisun marsh aster is a rare (CNPS 1B.2) California native perennial found in southern Sacramento Valley, Central Coast, and San Francisco Bay bioregions in marshes at elevations below 300 meters. Flowering from May to November, this plant produces violet ray flowers 8 to 14 millimeters long in open clusters. Growing with stems 40 to 150 centimeters tall that are nearly hairless, it spreads through long rhizomes. Its leaves are linear to narrowly lance-shaped, 5 to 15 centimeters long, sessile, and generally glabrous. The fruit is distinctively hairy.
Identification and appearance
Key characters: 4 sympatric species; marsh habitat and smooth tall stems with narrow leaves
Habitat and range
Habitat: Marshes
Elevation: < 300 m
Bloom period
Symphyotrichum lentum blooms May-Nov.
Conservation status
CNPS 1B.2
How to tell it apart
vs Corethrogyne: Corethrogyne has distinctive brown/reddish pappus; Symphyotrichum has white pappus; vs Erigeron: Erigeron has 50+ very thin rays per head; Symphyotrichum has fewer wider rays; vs Eurybia: Eurybia has two-toned bracts (green tips, white bases); Symphyotrichum bracts are all green; vs Aster: Aster is the old name for Symphyotrichum - they're the same plants; vs Dieteria: Dieteria has spinulose-tipped bracts; Symphyotrichum bracts lack spiny tips
Frequently asked questions
Is Symphyotrichum lentum native to California?
Yes. Symphyotrichum lentum is native to California (recorded as native).
When does Symphyotrichum lentum bloom?
Symphyotrichum lentum blooms May-Nov.
What plant family does Symphyotrichum lentum belong to?
Symphyotrichum lentum is in the Asteraceae family, genus Symphyotrichum.
Is Symphyotrichum lentum rare or endangered?
Symphyotrichum lentum carries California Rare Plant Rank 1B.2, state rank S2.
What habitat does Symphyotrichum lentum grow in?
Symphyotrichum lentum grows in Marshes.
Related species
Other California species in the same genus, family, or bioregion.
- Symphyotrichum occidentale — Western mountain aster
- Symphyotrichum occidentale var. intermedius — Larger western mountain aster
- Symphyotrichum occidentale var. occidentale
- Symphyotrichum occidentale var. yosemitanum — Western bog aster
- Symphyotrichum sp. — American-aster
- Symphyotrichum spathulatum var. spathulatum — Western mountain aster
Sources: Jepson eFlora · 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.