The state Department of Agriculture will limit its annual summer hunt for gypsy moths to Western Washington, opting to focus on catching plant-eating pests that arrived on ships or with new residents moving to the more populous half of the state, an agency official said Tuesday.

WSDA plans to hang 16,000 cardboard gypsy moth traps by the end of June, about 3,000 fewer traps than last year. The agency shares costs with the U.S. Department of Agriculture, which cut its contribution, WSDA Pest Program manager Jim Marra said.

With fewer resources, WSDA will forgo placing the traps in Eastern Washington, though the agency probably will next year, Marra said.

Washington State Tree Fruit Association President Jon Devaney said the one-year absence of traps is not an immediate concern, but the association hopes WSDA will periodically check to keep the moths from becoming established on the eastside.

European gypsy moths, indiscriminate leaf eaters, have defied decades of eradication efforts in the Eastern U.S. and Great Lakes region. Gypsy moths in 2014 defoliated 214,972 acres in Pennsylvania, according to that state’s Bureau of Forestry.

Washington and other states have adopted a no-tolerance policy to keep gypsy moths from advancing West.

WSDA last spring sprayed 220 acres in rural Clark County in southwest Washington, where 16 European gypsy moths were caught last summer. It was WSDA’s 93rd insecticide application since 1979 to kill the pests as they hatch. All but two of the applications were west of the Cascades.

Gypsy moths attach their eggs to outdoor surfaces. When attached to a motor vehicle or train, the eggs are easily transported cross-country. Over the years, most outbreaks have occurred in King and Pierce counties, the state’s two most populous counties.

Marra said WSDA also will concentrate traps at coastal ports to detect Asian gypsy moths, which have a greater potential to rapidly spread because the females can fly, unlike their European relatives. WSDA last sprayed for Asian gypsy moths in 2000.

WSDA also will do intensive trapping in rural Clark County to see whether the aerial spraying of Bacillus thuringiensis kurstatki (Btk) worked.

Another focus will be Seattle’s densely populated Capitol Hill, where last summer five moths were trapped within a block. WSDA decided not to spray because a search found no evidence of a reproducing population.

“We’re going to take a good, hard look at Capitol Hill. It is an area of concern,” Marra said.

WSDA will again this summer staff highway weigh stations to check moving vans traveling from the 19 states with gypsy moth infestations. Federal law requires movers to show papers certifying that they inspected goods for gypsy moth eggs.

Enforcement actions have not been taken against movers without the papers, but USDA sends a warning letter to the moving company, Marra said.

“The moving vans, we are finding, have a very high rate of non-compliance,” he said.