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the same way trees planted under conditions which cause 

 them to suffer during a spring drought may fall victims to the 

 bhot Borers, which can obtain a foothold during the time 

 when the trees are in a temporarily unhealthy state. It is 

 obvious, therefore, that the first line of defence is to keep up 

 * high standard of health by generally recognised measures. 



a. Although the dying tree is in an ideal condition for the 

 beetles, it becomes unsuitable when it has died and the wood 

 has dried up, with the result that first the Borer Beetles and 

 then the Bark Beetles are compelled to desert it. The insects 

 must then seek other quarters, and if very numerous they may 

 be compelled to attack not only sickly but also healthy trees 

 which fall victims solely because their enemies are in such 

 overwhelming numbers. It is therefore most important to 

 cut down and clear away all dying and badly damaged trees 

 or branches, burning them even if it is necessary to use other 

 dry wood to avoid delay in destruction. Tf they cannot 

 possibly be burned they should be carted far away Irom the 

 orchard. The beetles will come out freely for some time from 

 trunks and branches left lying about, for such wood does 

 not dry sufficiently rapidly to kill the brood inside. The best 

 cime to fell is during the first 'half of autumn for the insects 

 will not leave during the winter and there is thus time to get 

 the wood burned. All infested wood should have been disposed 

 oi by March at latest. 



3. In certain cases trapping may be useful against Shot 

 Borer Beetles. For instance after all badly affected trees or 

 branches have been burned, there may be left a number' 

 slightly attacked which it is desirable to save. In order to 

 give such trees as good a chance as possible beetles which 

 come out in the spring and are in search of fresh quarters may 

 be trapped. This should be done by providing them with wood 

 in an attractive condition as for instance, freshly cut oak 

 posts or plum trunks (unaffected by beetles) which may be 

 available owing to thinning or replanting, with better varieties. 

 The use of the stumps from which affected trees have been 

 c-ut has also been advised for trapping purposes. Whatever 

 may be used the traps should be in position by March, and 

 should be removed and burned about midsummer. 



4. Various preparations have been advised for brushing on 

 to the trunks and branches of trees attacked by Shot Borers. 

 They may either be of such a nature as to deter beetles from 

 beginning an attack or they may be intended to kill the fungus 

 in the burrows (upon which they feed). As the application of 

 these preparations is a difficult business in commercial orchards 

 and as the preparations themselves are more or less experi- 

 mental, no formulae are given here but thev can be supplied 

 if desired. It is suggested, however, that lime-wash properly 

 applied would have a considerable deterrent effect on beetles 

 in search of trees in which to start a burrow, and as such 



