CalWeedMapper is a new Web site for mapping invasive plant spread and planning regional management. Users generate a report for their region that synthesizes information into three types of strategic opportunities: surveillance, eradication and containment. Land managers can use these reports to prioritize their invasive plant management, to coordinate at the landscape level (county or larger) and to justify funding requests. For some species, CalWeedMapper also provides maps of suitable range that show where a plant might be able to grow in the future. The system was developed by the California Invasive Plant Council and is designed to stay current by allowing users to edit data.