The Willows out of Wollemi was a project that started with a goal of removing Black Willows from the Wollemi National Park by NPWS staff and volunteers and moved onto a volunteer Landcare program to remove Black Willows from the entire Colo Catchment. The project is still expanding to control Black Willows in adjoining catchments to prevent re-infestation of the Greater Blue Mountains World Heritage Area and Hawkesbury Floodplain Wetlands