THE ISSUE: Wild Buckwheat
Photo courtesy, Bruce Ackley, The Ohio State University, Bugwood.org
THE ISSUE: Wild Buckwheat
Wild Buckwheat (Polygonum Convolvus) is a summer annual weed found commonly in small grains. In wheat, wild buckwheat can reduce yields by up to 66%. In addition, wild buckwheat climbs up the shoots of plants causing difficulties harvesting and lowering the quality of the crop. In open areas, wild buckwheat can quickly become a problem as it shades out other, more desirable plants.
Wild buckwheat has a shallow root system and can grow up to 40 inches long. Many times, it is mistaken for field bindweed, but its arrow shaped leaves are more pointed. It has long, slender, creeping stems that trail along the ground until they encounter any object, which they immediately begin climbing. Their leaves are alternately arranged on the stem, are heart-or arrowhead-shaped, pointed at the tip, and have widely separated lobes at the base. The flowers have no petals but have five green or pinkish sepals. Flowers occur in short-stemmed clusters in the axils of the leaves or at the end of the stem.
Integrated Pest Management (IPM) Options:
• Cultural – practices such as crop rotation and delayed seeding can reduce incidence of wild buckwheat but will not provide effective control.
• Mechanical – Mowing, post-seeding harrowing, post-harvest cultivating can also reduce incidence but will not provide effective control. Tilling can encourage germination, performing another tillage operation after seedlings germinate will kill seedlings. On small infestations hand pulling can be successful if done faithfully. Ensure you pull the whole root to avoid regrowth.
• Chemical – Spraying early for wild buckwheat is the most effective method of control. There are several effective herbicides available. To avoid resistance to herbicides, use a combination of chemical groups and rotate between differing modes of action. For more information visit https://pnwhandbooks.org/ then search “wild buckwheat” in the weed section. Always read and follow herbicide label directions!
Tom Jacobsen, University of Idaho Extension Educator in Fremont County. (208) 624-3102 [email protected] and Justin Hatch, University of Idaho Extension Educator in Caribou County. (208) 547-3205
