cockleburs

genus Xanthium

Member of sunflower family (family Asteraceae)
dicots (class Magnoliopsida)
flowering plants (subphylum Angiospermae)

There are no other wild species of this genus in California.

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spiny cocklebur
Xanthium spinosum

• golden spines at nodes, with generally 3 branches, 15–30+ mm long
• leaf abaxially minutely coarse-hairy

common cocklebur
Xanthium orientale

• no nodal spines
• leaf abaxially densely strigose

Toxicity of cocklebur (Xanthium spp.):
1 – Skin contact with these plants can cause symptoms ranging from redness, itching, and rash to painful blisters like skin burns.
3 – Ingestion of these plants is expected to cause nausea, vomiting, diarrhea and other symptoms that may cause illness but is not life-threatening.

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1 observed taxon / 2 unobserved taxons / 1 key

Chris’s observations: 3 (none are research grade)

Locations:

• Henry Coe SP
• Lake Chabot RP
• Mt. Diablo SP

Months:

• May: 1
• Jun.: 0
• Jul.: 0
• Aug.: 0
• Sep.: 0
• Oct.: 0
• Nov.: 2

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Taxon info: iNaturalist – Calflora – Jepson eFlora – FNA

Bay Area species: iNaturalist – Calflora