Katydids are insects in the grass hopper family. They are well camouflaged on trees and shrubs in New Zealand gardens. Although they eat leaves they are rarely a significant pest.
Identify the problem
Katydid adults are usually green with large leaf shaped bodies to make themselves well hidden in among plant foliage. However, there are occasionally katydids of other colours as they can pick up the colour of what they are feeding on. Nymphs are more grasshopper-like in appearance.
Katydids rarely do significant damage to garden roses, trees and shrubs. They can attack developing citrus fruit. If damage is occurring it is helpful to remove long grass around the affected plants as it is in long grass that katydids hide at night.