What's eating my iris pseudacorus 'variegatus'?

Iris pseudacorus 'Variegatus' (yellow flag iris) is most threatened by iris sawfly larvae, which shred leaves rapidly in spring. Slugs and snails attack soft new growth, aphids cluster on stems, and iris borer tunnels into rhizomes in North America. Inspect early in spring and act fast on sawfly.

Larvae notch and shred leaf margins, reducing leaves to ragged strips from late spring onward Hand-pick larvae daily; knock into soapy water. Remove egg clusters from leaf edges in early spring. Neem oil spray as a deterrent.

Irregular holes and silvery slime trails on new shoots and soft leaf bases Apply iron phosphate pellets around the pond margin; set beer traps; collect at night. Avoid excess mulch.

Tunnels through leaves and rhizomes, leaving slimy, foul-smelling rot; mainly a US pest Cut and destroy affected leaves in autumn; crush eggs on old foliage. Apply beneficial nematodes (Steinernema carpocapsae) to soil in spring.

Sticky honeydew, curled or yellowing stem tips, colonies on flower stalks Blast off with a strong water jet; introduce ladybirds/lacewings. Insecticidal soap spray if infestation is heavy.