DULUTH — The state plans to impose a quarantine to limit the spread of destructive gypsy moths and it will affect travelers visiting Lake and Cook counties in northeastern Minnesota, agriculture officials announced Thursday.

This is the first time the state has imposed a quarantine to try to contain gypsy moths, the Minnesota Department of Agriculture said. The invasive insects, which are among America’s most damaging tree pests, were caught in record numbers along the North Shore of Lake Superior last year. Traps caught 71,258 gypsy moths, and 90 percent of them were located in the two counties in the state’s far northeast. Insecticide treatments have become ineffective against them.

Under the proposed quarantine, outdoor items in the quarantined counties that could be infested with gypsy moth hitchhikers — such as logs and firewood, recreational vehicles, camping equipment and patio items — must be inspected and certified as gypsy moth-free before they’re moved to a non-quarantined area. People would be required to conduct a self-inspection with an official checklist or use a certified inspector.

“We knew the day would come when a gypsy moth quarantine would be needed to contain the insects’ spread in Minnesota,” Geir Friisoe, director of the department’s Plant Protection Division, said in a statement.

“Cooperation among everyone in the Arrowhead now and into the future will be needed to help slow the gypsy moth and protect Minnesota’s natural and urban forests,” Friisoe said.

The department will open a 30-day comment period Monday and plans two public hearings, Feb. 11 in Two Harbors and Feb. 25 in Grand Marais. The quarantine is scheduled to take effect March 31.