SHE-OAK ROOT BOKER. 115 



CHAPTER CXXVII. 



SHE-OAK ROOT BORER. 

 (Stigmodera heros, Grehin.) 



Order : Coleoptera. Family, Buprestidce. 



This formidable insect, which is the largest of the 

 Victorian Buprestid beetles, is most destructive to various 

 kinds of timber growing mostly in the northern and 

 north-western portions of the State. It is also found in 

 South and Western Australia. The larva feeds in She-oak 

 and Bull-oak (Casuarina), and frequently in the Eucalypts 

 growing in or near the Mallee country. 



The larvae of these beetles are large yellowish white 

 grubs, with powerful jaws, the female beetle being much 

 larger than the male. The female clears spaces in the 

 butts of trees and deposits her eggs, which are somewhat 

 lighter in colour than the grub, on the side of the trees. 

 When hatched, the young larvae at once commence to 

 eat their way into the wood of the tree attacked. After 

 working downwards to a depth sometimes of several feet, 

 the larvae bore and tunnel into the wood, the sawdust of 

 which serves as food for the grubs. Judging from the 

 quantity of excreta formed, and from other indications, 

 it would appear that in many cases the larval stage lasts 

 as much as two years, or even more. It is suspected that, 

 in comparison, the pupal stage is of short duration. When 

 the perfect insect emerges into a large yellowish- brown 

 beetle, it may be found in large numbers feeding in the 

 flowers of the stunted Mallee, also in the Melaleuca, a twig 

 of which, together with the beetle, is reproduced. 



When fully developed, the larvae of these beetles have 

 small but very powerful mandibles or jaws, and with these 

 they can gnaw almost any kind of timber, no matter how 

 hard it may be. 



