110319LangrallcolumnP1

Burdock photographed by George Chernilevsky, courtesy Wikimedia Commons

Hikers know it and bicyclists loathe it. It’s that ungainly weed that offers little in the looks and fragrance department, and according to most people who have come into direct contact with the plant, it is one they could live without.

Burdock has a bad reputation that comes from its menacing habit of attaching itself to anything it touches, from animal fur to clothing, and even bike tires. While their large heart-shaped leaves make the plant seemingly harmless, their small flowerheads can catch you off guard. These bright pink or purple flowers are striking enough to be mistaken for the milk thistle plant. Although there is some similarity and milk thistle and burdock are in the same Asteraceae family, they have different genuses: milk thistle is Silybum, and burdock is Arctium.

The trouble really starts when outdoor enthusiasts and wildlife get too close, causing severe frustration and even death — birds that become entangled in the burrs can suffer a slow death as they are unable to free themselves. The fruits (flowerheads) contain small bracts with hooked spines curving inward, forming prickly burrs that are extremely difficult to remove once they find their new home. According to the Native Plant Atlas, burdock has become a problematic invader of pastures, hay fields, and open prairie ecosystems. It is a host for pathogens like powdery mildew and root rot that threaten other important, native plants. If cattle overgraze burdock, their milk can become tainted and the seed heads that get stuck in sheep’s wool can have dire economic consequences for farmers and ranchers.



Tags