: Symphytum officinale ssp. uliginosum, Symphytum uliginosum
: Knitbone, boneset
: Introduced to North America in the 1600s for its medicinal properties. Now, products containing comfrey are illegal in the United States due to the alkaloids it contains. It is capable of causing fatal liver toxicity and plays a role as a cancer causing agent.
: Large, coarse, tuberous, clumping perennial capable of growing up to 3 feet tall.
: Basal leaves are large, pointed, hairy, ovate-lanceolate, dark green in color and grow to about 8 inches long. Upper leaves are decurrent, smaller. Mature leaves are winged.
: Green in color, hairy, erect to ascending, clump forming, branched.
: Tubular, 1/2 long, bell-shaped; white, pink or purple in color, 5 shallow lobes, borne in drooping clusters. Calyx and stalks are covered in bristly hairs.
Fruit and seeds
: Cluster of 4 nutlets maturing to shiny brownish-black in color.
: Native to Europe and Asia. Can be found in roadsides, ditches, fields, yards and disturbed sites.
: By seed and vegetatively by root fragments or division.
: Tall bluebells (Mertensia paniculata
Monitoring and rapid response
: Very difficult to remove by hand as any root fragment left behind can easily resprout.
: The information provided in this factsheet was gathered from the Missouri Botanical Garden and Minnesota Wildflowers.
Individual species images that appear with a number in a black box are courtesy of the Bugwood.org network (http://www.invasive.org).Individual photo author credits may not be included due to the small display size of the images and subsequent difficulty of reading the provided text. All other images appear courtesy of Google (http://images.google.com).