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Alder nitrogen-fixing symbiont

Frankia alni

Nitrogen-fixing bacterium symbiotic with native alder trees. Improves soil fertility in riparian zones. Essential for native watershed restoration.

Plants that support Alder nitrogen-fixing symbiont

2 plants

California Alder

Alnus rhombifolia

critical

tree

obligate symbiotic relationship in root nodules; critical for alder nitrogen fixation and riparian ecosystem productivity

Bay Area nativeKeystone species

Red Alder

Alnus rubra

critical

tree

Forms critical nitrogen-fixing nodules in alder root systems; essential for riparian soil health

Bay Area nativeKeystone species