INSECT PARASITES AND PREDATORS OF INSECT PESTS 7 



While the Australian ladybird beetle is very effective in controlling 

 mealybug infestations under orchard conditions, it is of little or no 

 value for use in greenhouses. The reason for this lies in the fact that 

 a fairly heavy infestation is necessary before the beetle is able to in- 

 crease rapidly. Orchard trees can stand this degree of infestation 

 with relatively little injury, whereas greenhouse plants are seriously 

 injured, or at least their market value is greatly reduced. The dam- 

 age is done before the infestation becomes sufficiently great to permit 

 of the increase of the beetle, and for this reason it is necessary to rely 

 upon spraying or fumigation for control. 



Many inquiries are received from residents in the mountainous 

 sections of the West who have noted colonies of aphid-feeding lady- 



Figure 3. — Pupae of the Chinese ladybird beetle (Chilocorus similis) in typical clusters 

 on twigs. Those at left are natural size. 



bird beetles and wish to be advised as to a possible market for them. 

 These beetles at present have no commercial value, although occa- 

 sionally quantities are required for experimental purposes. This de- 

 mand, however, is so small as to be negligible, and returns are seldom 

 sufficient to defray the cost of collection and shipment. The presence 

 of these beetles in such quantities in winter quarters indicates, that 

 they occur in large numbers in the orchards and fields in those sections 

 during the spring and summer months. There is no advantage to 

 be gained by the liberation of additional numbers in orchards where 

 the beetles already occur. In general, these beetles appear in all 

 sections in which the aphid infestations give them an opportunity to 

 develop. The liberation of large colonies for the field control of 

 aphid infestations is not recommended. 



