Purple loosestrife is an attractive wetland perennial plant from Europe and Asia that was introduced to North America without the specialized insects and diseases that keep it in check in its native lands. Freed from its natural controls, purple loosestrife grows taller and faster than our native wetland plants. These advantages and prolific seed production have allowed it to invade many Wisconsin wetlands to the near total exclusion of most other vegetation. Loosestrife has spread rapidly in Wisconsin over the last 20 to 30 years. This brochure describes how to identify and manage purple loosestrife.