Yellow Flag Iris vs Cattail Identification

Learn how to identify and tell the difference between the invasive Yellow Flag Iris and the native Cattail. Yellow Flag Iris is invasive in North America. Yellow flag is native to temperate regions of Europe, Asia, and northern Africa. It was imported to North America as an ornamental plant as early as the late-1700s. The plant has since been deliberately propagated as a horticultural plant and for erosion control and in sewage treatment ponds.