Yellow Flag Iris
Yellow Flag Iris is an aquatic perennial which grows up to 2 metres tall and originates from Europe and North Africa. It has yellow flowers which form brown seed capsules and dense rhizomes. It is poisonous to humans and animals and forms dense mats that displace native vegetation and increase the risk of flooding.
Infestations of Yellow Flag Iris can be found in many waterways on the Wairau Plains in Marlborough.