plumeless thistles

genus Carduus

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

There are no other wild species of this genus in the bay area.

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Key features:

• number of heads per cluster
• width of involucre
• width and hairiness of phyllary bases

musk thistle
Carduus nutans

• heads generally solitary, conspicuously peduncled
• involucre 2–7 cm diameter
• phyllaries generally > 2 mm wide
• La Honda Creek

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2 observed taxons / 1 unobserved taxon / 1 key

Chris’s observations: 21 (14 are research grade)

Locations:

• Russian Ridge OSP: 4
• Calero CP: 3
• Coyote Hills RP: 2
• Henry Coe SP: 2
• Almaden Quicksilver CP
• Coyote Lake / Harvey Bear Ranch CP
• El Corte de Madera OSP
• Monte Bello OSP
• Mt. Diablo SP
• Santa Teresa CP
• Sibley Volcanic RP
• Sierra Azul OSP
• Stevens Creek CP
• Wilder Ranch SP

Months:

• Apr.: 5
• May: 11
• Jun.: 4
• Jul.: 0
• Aug.: 0
• Sep.: 0
• Oct.: 0
• Nov.: 1

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Taxon info: iNaturalist – Calflora – Jepson eFlora – FNA

Bay Area species: iNaturalist – Calflora