Introduction This TreeNote describes the most significant insect pests for eucalypts and pines in southern Western Australia and lists insecticides to control them.
Insects can damage all parts of trees at every stage of tree development.
However, most trees are host to a range of insects throughout their life and cope well with minor insect damage. Trees are attractive to insects because they can provide shelter, as well as a range of food sources for larvae and adults. Some insects feed on leaves, while others feed on new shoots, stem tissue, roots, sap, flowers or seeds. Some shelter in or between leaves, while others shelter in or under the bark, or bore holes in the wood. Because these factors vary through time, insect numbers can fluctuate widely, occasionally producing a population explosion.