Thank you for contacting the Growline [Cornell. Cooperative Extension Tompkins County]. I’m sorry to hear you have a goutweed infestation. Goutweed (Aegopodium podagraria), aka Bishop’s weed and Snow-on-the-Mountain, was introduced from Europe and Northern Asia in the mid 1800s. In the middle ages, monks cultivated it for treating gout; hence the name. It thrives in moist, well drained soils in partial sun to full shade. The plant spreads by fast growing underground roots (rhizomes) as well as seeds.
Eradication of this plant takes persistence but can be done. First, remove any flower heads before the plant goes to seed to prevent seed production. Cut and bag the flowers.
There are several additional strategies you could employ: