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to the ravages of termites, or white ants, in Australia, it would probably be found 

 that these insects hold a place unrivalled by any in economic importance. 



Broadly speaking the habits of all species are very similar. The popular 

 acquaintance with the termite or white ant is mainly derived from witnessing the 

 nights of the winged forms of this pest. They emerge from cracks in the ground 

 or from crevices in buildings, swarming out sometimes in enormous numbers. These 

 winged individuals are not the ones that do the damage, but are the colonising 

 forms. The real depredators are soft bodied, large headed, milky white insects, 

 which are found under cover in tree trunks, logs, stumps, walls, and floors of build- 

 ings, etc. These are the workers and soldiers. 



The food of white ants is the finely divided material into which they bore and 

 from which they seem able to extract nourishment. White ants are somewhat can- 

 nibalistic and will devour their own cast skins and dead. It is this habit that 

 largely aids in the poisoning of a nest. Those that die from the poison are eaten 

 by the remaining members of the nest and they in turn are poisoned. White ants 

 cannot endure bright light. In all their operations, therefore, they carefully con- 

 ceal themselves. In this way the damage which they may be doing is often entirely 

 hidden until perhaps a tree is blown down, w 7 hen their work of quiet destruction 

 is revealed. There are many other forest insect pests that cannot here be dealt 

 with. 



PEINCIPAL MEASURES OF CONTROL. 



The ordinary spraying and similar methods employed in dealing with fruit 

 and shade tree insects are, of course, not available for practical application in the 

 case of forest trees. 



In all efforts to control an outbreak or prevent excessive loss from forest in- 

 sects it should be remembered that as a rule it is useless to attempt the complete 

 extermination of a given insect enemy of a forest tree or its product when once 

 widely established. Our efforts must be directed to reduce the conditions which 

 favour the undue increase of a pest, that may result from forest mismanagement 

 or negligence. Under complete forest sanitation, we can in a large degree prevent 

 the favourable conditions for destructive insect propagation, and can aid in the 

 propagation of beneficial insects, animals, and birds. 



Were it not for the natural checks and natural factors of control of some of 

 the more destructive insect enemies of forest trees and products, artificial control 

 in many instances would be impossible. The insects and birds which prey upon 

 destructive insects are also themselves subject to natural enemies and have there- 

 fore their limitations for good. 



We can best assist our natural insect and bird friends in their efforts to main- 

 tain the balance of nature by our alliance with them, in adopting all measures which 

 will weaken the forces of insect depredation, below the power of making an ag- 

 gressive outbreak. This is largely accomplished by the destruction by cutting and 

 burning of insect infested trees. This must be done at the right season, and hence 

 it is necessary to know the life history of the pest before control measures can be 

 suggested. It is of no avail to burn a tree after the pest which caused its death 

 has issued. Trees planted or growing in unhealthy conditions will be more sub- 

 ject to insect invasion than trees which are planted in healthy localities. There- 

 fore, unhealthy trees are better destroyed and only trees pi anted that will tolerate 

 the conditions. As far as possible all forests should be kept in a healthy condition 

 by good drainage and the prevention of fires. Fires are largely avoided by the 

 creation of fire breaks. These are cleared narrow strips of country which divide 

 the forests into given areas and thus make it possible to confine a fire, should it 

 break out, to the one block. Trees damaged by fire or other artificial means are 



