A public meeting in Covington later this month will be part of an effort by King County officials to enlist citizens’ help to protect riversides from knotweed.

With state and federal funding and the support of landowners and public-land managers, the county’s noxious-weed program is leading a cooperative effort to get control of what officials call a tough, fast-spreading plant.

“Knotweed spreads when floods move root fragments downstream, so control involves starting at the top of the waterway, then moving downstream and systematically removing all knotweed in the floodplain,” said Steven Burke, program manager.

He said knotweed harms fish and wildlife habitat along rivers.

Knotweed is controlled by injecting an herbicide directly into the plant’s hollow stems or by reducing the roots.

Officials said landowners can get detailed information on knotweed removal during a meeting July 15 from 7 to 8:30 p.m. at the Covington Library, 27100 164th Ave. SE. A similar meeting was held June 24 at Maplewood Greens.