Also known as bishop’s-weed and snow-on-the-mountain, goutweed is native to Europe and northern Asia. Goutweed has a tall thin stem with dark green to blue-green basal, toothed leaves and small, white five-petaled flowers that bloom in mid-summer. Capable of growing in dense patches, this weed displaces natives and is often responsible for the absence of young conifers and other native tree species.
Goutweed can be found in deciduous and southern boreal forests in several states throughout the Northeast, the mid-Atlantic, and the Northwest, usually taking hold in disturbed areas such as pastures, felled forests, or abandoned fields and gardens. Goutweed was brought to North America as an ornamental in the 1860’s, and the leaves were also commonly used in salads.
This plant spreads more from its extension of existing plants through rhizomes (underground stems) than from seed, which can make removal a lengthy process, as these rhizomes can come through the ground years after the plant is removed. However, chemical treatment (glyphosate-based herbicides seem to work best) can be effective in killing the whole plant, and persistent manual treatment in smaller patches is also effective. Frequent mowing can usually keep an infestation from expanding or becoming any worse. It also helps if native alternatives are planted shortly after treatment, so they can re-establish.