Description from Prairie Moon Nursery: Canada Milk Vetch is a common plant found throughout the US and Canada. This adaptable species can thrive in a variety of environments including prairies, woodlands, and stream banks. As a garden plant, Canada Milk Vetch provides great leaf texture. The green flowers make an interesting addition to cut flower arrangements. Canada Milk Vetch is a common nectar source for bumblebees and honeybees, and for food for animals including deer, wild turkey, groundhogs, rabbits, and livestock. Also called Canadian Milk Vetch, or Rattle Weed, it attracts hummingbirds, song birds, and butterflies, including the Western Tailed Blue Butterfly larvae. Astragalus species are also one of the host plants for the Clouded Sulphur butterfly.
Although generally not considered poisonous, caution is advised with any member of the Astragalus genus as they are known to contain at least some level of toxic glycosides.
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