White Snakeroot, Ageratina altissima

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Wild Golden Glow
Wild Golden Glow
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White Snakeroot

( Ageratina altissima ) Bloom Time: Summer – Fall (July – October) Location: prefers shady, moderately moist deciduous woods. Beyond this, A. altissima is not too discriminating, and will grow in thickets, edge habitat, bluffs, meadows, riparian zones, hedgerows, and vacant lots. It does prefer more disturbed soils, but will grow in isolated, higher quality areas (general). Common throughout all woodlands in the Cowling Arboretum (Arb). Family: Aster (Asteraceae) Physical Description: blooms are clusters of several small white flower heads composed of even smaller five-petaled disk flowers. Each of these disk flowers has a long, white style. Opposite leaves are long (up to 6 in.), coarsely toothed, and distinctly veined. Grow to be 1-4 ft. tall. NOTE: this plant is toxic and should not be consumed. Contains the toxin trematol, which can be fatal to humans. Historically, the illness caused by this plant was called “milk sickness”, as cows that consumed it produced milk with trematol.


Peter M. Dziuk