Idaho Fish Report

Invasive weed treatment at Cape Meares Lake July 13

July 12, 2023

TILLAMOOK, Ore. — Cape Meares Lake will be treated to remove aquatic invasive weeds on Thursday, July 13. Eurasian water milfoil has taken over the lake and is inhibiting fishing and other recreational activities.

An aquatic herbicide will be applied by a licensed contractor to kill the weeds in the lake. The herbicide specifically targets the broadleaf aquatic invasive weed and is not harmful to fish, animals, people or other aquatic plants.

ODFW will post signs and people should stay off the lake during the treatment on Thursday to not disrupt the application.

Lake water should not be used to irrigate broadleaf plants for 7 days after the treatment (until July 21).

This is the first of two applications (about half of the lake each time). The next treatment will occur in about 3 weeks to give time for the plants to decompose and also to avoid lowering dissolved oxygen levels in the lake.

This is a cooperative project led by ODFW with Tillamook County in response to requests from anglers and local residents to respond to the weed outbreak.