Ragwort
Jacobaea vulgaris, synonym Senecio jacobaea, is a very common wild flower in the family Asteraceae that is native to northern Eurasia, usually in dry, open places, and has also been widely distributed as a weed elsewhere.
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Research Mentions
Toxic invasive ragwort spotted growing along a Portland roadside
If you keep horses, goats, or cattle near Portland, this yellow-flowered weed can poison your pas...
Toxic invasive ragwort confirmed spreading in Portland yards and lots
That cheerful yellow weed popping up in vacant lots and along sidewalks is toxic to horses, cattl...