Goutweed

Also known as Ground Elder, Herb Gerard, Bishop's Weed, Wild Masterwort

Goutweed blankets shady forest floors and disturbed garden beds with a dense subterranean network of aggressive rhizomes that crowd out native flora. In late spring and midsummer, upright hollow stems rise above the foliage to unfurl broad, flat-topped umbels of tiny white flowers that attract a diverse array of hoverflies and solitary bees. Monks once cultivated it across medieval Europe as a medicinal treatment for joint pain and gout, but its vigorous vegetative spread has earned it a reputation as an intractable garden weed.