By BROOKE KNICK, Natural Resources Conservation
Soil Conservation Technician
The other day, a lady was proud to show me her patch of wild rhubarb that just popped up this year. However, after I flipped the leaf over to see the white underside, I had to inform her that her “wild rhubarb” was actually burdock. Burdock produces cockleburs which stick in your socks, your shoelaces, and your dog.
Burdock is a Minnesota secondary noxious weed that spreads rapidly. In its first year of growth, these small heart-shaped leaves will cluster into basal rosettes. If allowed to continue to grow to the second year, this rhubarb-resembling mound will bolt up to six feet, flower and begin to produce seeds. Each plant can produce up to 18,000 seeds. Seeds are viable up to three years.
Burdock seeds are surrounded by prickly barbs that easily attach themselves to soft clothing and animal hair. The barbs of burdock are so effective, that they were the inspiration for Velcro in the early 1940’s. And after taking the dog for a walk, it might become a common practice to pick the burs out of his coat and throw them on the ground. But that only helps the weed spread faster. Instead, consider tossing them into the trash or the burn barrel.
Burdock is commonly seen along river banks, fence-lines, woodland edges, waste areas, and (thanks to the dog) in lawns and landscaped areas. It can be easily controlled by hand pulling and broadleaf herbicides. Be sure to wear gloves when handling burdock, because the leaves and stems produce lactones which may cause inflammation to the skin. In our heavy soils, a shovel can be used to dig out young plants. Once the plants are larger, digging is very difficult, since taproots can grow one to two feet deep. If the tap root is cut with a shovel, the plant can grow back similar to a dandelion.
But don’t spray the rhubarb patch thinking it’s full of burdock. The two different plants can easily be distinguished. The underside of the burdock leaf is covered with tiny hairs. In some cases the hairs cause the underside of the leaf to look silver. Rhubarb doesn’t have any hairs. Burdock root is edible though. Young roots are cultivated as a vegetable crop in Japan.
Financial assistance for burdock control is available to agricultural producers on non cropland acres through the Environmental Quality Incentives Program. Assistance to other landowners may be available through the Lake of the Woods Soil and Water Conservation District. For further information, please contact the SWCD/NRCS office at 218-634-2757 ext. 3.
For more information on Burdock visit http://www.oardc.ohio-state.edu/weedguide/singlerecord.asp?id=900
