The meadow is a vibrant and diverse ecosystem, home to a wide variety of native plants. But non-native species like the yellow flag iris can also take root and quickly spread. This plant, with its large, colorful blossoms, was introduced in the late 1700s as a decorative plant. Unfortunately, it’s also very invasive. Yellow flag iris pushes out aquatic plants like cattails and native irises, such as the dwarf-crested iris and the blue flag iris. It’s resistant to deer and other wildlife, so it can quickly take over an area.