alders

genus Alnus

Member of birch family (family Betulaceae)
dicots (class Magnoliopsida)
flowering plants (subphylum Angiospermae)

Caution: There are other wild species of this genus not yet included in this guide.

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There are more alders in the bay area that may or may not be wild, but these are by far the most common ones.

Hosts Dasineura alnus-fold-gall.

Toxicity of alder tree (Alnus spp.):
1 – Skin contact with these plants can cause symptoms ranging from redness, itching, and rash to painful blisters like skin burns.

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2 observed taxons / 1 key

Chris’s observations: 8 (5 are research grade)

Locations:

• Murray Ranch SP: 5
• Lake Chabot RP
• Sierra Azul OSP
• Stevens Creek CP

Months:

• Jul.: 3
• Aug.: 3
• Sep.: 0
• Oct.: 0
• Nov.: 2

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Taxon info: iNaturalist – Calflora – Jepson eFlora – FNA

Bay Area species: iNaturalist – Calflora