An update on successful efforts to fight this plant, and what you can do to help
As its name suggests, Japanese butterbur hails from Japan where some people consider it edible with careful preparation. Some parts of the plant are poisonous. Its scientific name comes from the Greek word, meaning a wide brimmed hat.
Japanese butterbur’s kidney-shaped leaves can be up to four feet wide and are fuzzy on the underside. It emerges in late winter or early spring, sometimes with clumps of white or pale yellow flowers appearing before the leaves, and can grow up to six feet tall.
Japanese butterbur spreads mostly through underground stems, and sometimes through seeds. It seems to be spreading in Portland through yard waste dumping, plant trading and when the underground stems break apart and float down streams. Gardeners sometimes plant Japanese butterbur in containers to check its spread, but this plant is an escape artist! It’s been known to spread in spite of containment.
Hand-pulling is an effective way to remove small areas of Japanese butterbur from your yard, though you’ll have to continue pulling sprouts for at least a few years. Mowing will not remove the plant but can keep it from spreading. More established populations are difficult to control and common herbicide treatments don’t seem to be effective. If you find Japanese butterbur, please contact at Environmental Services to discuss control options.