Iris pseudacorus Yellow Iris

A very common, well known, yellow-flowered, rhizomatous iris of marshes, wet woodland, ponds, canals and other wet places. It is found almost everywhere in suitable habitats in the lowlands of Britain. Its large, bright yellow flowers earned it the frequently used name of Yellow Flag and its Welsh name, Baner y Gors, means bog-flag. The official name, Yellow Iris, seems rather prosaic in comparison. It has a predominantly lowland distribution in West Glamorgan, where it is a common feature of marshy areas in Gower and along the canals of Neath Port Talbot, which is illustrated well in its distribution map. Most parts of the plant contain toxic isoflavones, the most important of which is iridin that is toxic to most vertebrates, but not to some invertebrate species such as the Iris Sawfly (see photo).

Native