rayless arnica

Arnica discoidea

Member of genus Arnica
tarweeds and allies (tribe Madieae)
sunflower family (family Asteraceae)
dicots (class Magnoliopsida)
yellow in flowering plants

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• heads discoid
• uncommon

Toxicity of arnica (Arnica spp.):
1 – Skin contact with these plants can cause symptoms ranging from redness, itching, and rash to painful blisters like skin burns.
4 – Ingestion of these plants, especially in large amounts, is expected to cause serious effects to the heart, liver, kidneys or brain. If ingested in any amount, call the poison center immediately.

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Chris’s observations: 2 (all are research grade)

Locations:

• Castle Rock SP
• Sam McDonald CP

Months:

• Jun.: 1
• Jul.: 1

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Taxon info: iNaturalist – Calflora – CalPhotos – Jepson eFlora – FNA

Bay Area species: iNaturalist – Calflora