A suburban Chicago official says hundreds of fish died in the community's lake when oxygen levels plummeted after an herbicide was applied to combat aquatic plants.
About 400 fish, including largemouth bass, died last week in Libertyville's Butler Lake soon after a company applied a chemical that's designed to control invasive weeds, including the lake's excessive growth of water lilies.
Libertyville public works director Paul Kendzior tells The Daily Herald that the vegetation die-off caused dissolved oxygen levels to fall, depriving fish of oxygen and killing them. He says the herbicide application itself didn't directly harm the fish.
The Illinois Department of Natural Resources plans to survey the lake's fish this fall.
St. Charles-based Clarke applied the herbicide, which the company says is approved for aquatic use.