VANCOUVER, Wash. (AP) – Plans to treat Eurasian milfoil at Vancouver Lake have been delayed because the invasive weed has stopped growing and would no longer effectively absorb an herbicide.

The Columbian reports that friends of Vancouver Lake, which has raised private and public dollars to treat the infestation, announced Monday that treatment will be delayed until the late summer or spring of 2020.

AquaTechnex, a Centralia-based company that specializes in invasive species control and toxic algae management, was scheduled to treat the lake’s milfoil with ProcellaCOR this week.

The company’s manager, Terry McNabb, said cyanobacteria blooms, also known as blue-green algae, likely have prevented daylight from penetrating the lake, which has halted the milfoil’s growth.