PEST
 
   NAME
     Stick and Leaf Insects (General)
     Various Stick Insect Species
 
   ORDER
     Phasmatodea

Description of the Pest
There are many species of leaf or stick insect all are unusual looking and are greenish or brownish colour. The stick insects are long slender up to 200mm long and resemble sticks and leaf insects imitate living or dead leaves. They move slowly through the host plant and eat entire leaves. 

The Brown Stick Insect (Ctenomorphodes tessulatus) is a slender, brown and up to 120mm long. The very slender male is winged and the female is wingless, feeding solitary or in small groups.

The Large Stick Insect (Didymuria violescens) is brown growing to 180mm long and only the slender male is winged. It also feeds in solitary or in small groups eating entire leaves.

The Ring-barker stick insect (Podacanthus wilkinsoni) has a shorter thicker body with long antenna, legs and wings with an orange colouring, growing to 80mm long. Normally found feeding in groups stripping trees.

The Spiny Leaf Insect (Extatosoma tiaratum) is a spiny bright green insect with flat leaf-like plates on the upper surface of the abdomen and legs. It has a prominent head with two slender antennae and feeds solitary on the leaves.

Life Cycle
These insects have a Hemimetabolous life cycle, ie. When the immature nymphs resemble the adults.
The life cycle involves several wingless nymphal stages and the adults may or may not be winged. 

Period of Activity
Many of these insects are found in tropical to sub tropical climates and are present throughout the year, while others are found in temperate climates and are active during the warmer months.

Damage Caused
Leaf and Stick Insect strips leaves or bark from the host tree. Stick insects in particular can occur in large numbers devastating large areas of trees. The Ring-barker stick insect attacks the leaves and the bark causing dieback or the branches.

Susceptible Plants
Many plants are attacked by these insects including Eucalyptus and Acacia species, Allocasuarina littoralis, Lophostemon confertus and Syncarpia glomulifera.

Cultural Control
Small infestations may be removed by hand and normally cause insignificant damage in domestic gardens.

Biological Control 
These insects are eaten by many birds, lizards, frogs, patristic wasps and predatory bugs.

Chemical Control
Spraying in a small garden is not normally warranted, but application of contact insecticides when first seen will kill them. 
Note
Always read the label for registration details and direction of use prior to application of any chemicals.