Iris pseudacorus

yellow flag iris - This showy European native gives new meaning to the phrase “attractive nuisance.” First planted in the 1800s as a splash of color along pond edges, stream banks, and other moist areas, the deep blue-green sword-like leaves and lemony yellow flowers of yellow flag iris are now found far from cultivated gardens and domestic ponds, energetically colonizing wild wetlands where they can displace native irises. Yellow flag iris is easily distinguished from native irises because it is the only yellow-flowered iris species growing in the wild. Because it readily spreads both from seed and by division, digging or pulling the whole plant is advised. [image: (c) New England Wild Flower Society/Dorothy Long]

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