Arundo donax photo by wikipedia user H. Zell under Creative Commons License

Madera County officials are working to eliminate a dangerous invasive species that increases flooding and wildfire risk.

A state-of-the-art abatement project is underway to remove Arundo donax, a tall perennial grass that forms dense stands and outcompetes native plants, according to county officials. The project will clear flood control channels to reduce future floods and wildfire risk and improve water supplies for Madera residents.

The effort aims to remove large tracts of the weed, which can grow up to four inches a day and as tall as 30 feet. Highly flammable, it can cause major damage to public and private property by clogging waterways and forcing floodwater to overtop infrastructure.

The removal follows a detailed, noninvasive drone mapping process completed last month.

Madera County and the nonprofit river restoration organization River Partners are teaming up to help landowners remove Arundo through a free program targeting properties along Ash Slough, Berenda Slough, the Chowchilla River, Dry Creek and the Fresno River.

Work began last week and will continue through the end of the grant in March 2026, with the potential for future expansion pending landowner approval.

Removal involves a combination of mechanical methods and water-safe chemical treatments to eradicate the weed, which is difficult to control and contributed to major flooding along these waterways during the severe winter of 2023.

Landowners with questions about the free program can contact River Partners at (559) 481-1171.