State biosecurity teams are ramping up efforts in Perth’s northern wetlands to prevent the spread of the declared weed Noogoora burr. State biosecurity teams are ramping up efforts in Perth’s northern wetlands to prevent the spread of the declared weed Noogoora burr. Credit: Supplied / Photographer Peter Maloney CopyrState biosecurity teams are ramping up efforts in Perth’s northern wetlands to stop a toxic weed from spreading. A joint inspection operation is now under way at Yellagonga Regional Park, around Lake Joondalup, to target the invasive weed Noogoora burr (Xanthium strumarium), led by teams from the Department of Primary Industries and Regional Development and the Department of Biodiversity Conservation and Attractions. More information on the invasive weed can be found on the DPIRD website.