150 ORCHARD INSECTS 



a few days to reach, maturity and as each adult female will 

 produce several young in a day, they increase with great rapidity. 

 This makes their control a serious matter. 



Control. Now, what shall be done to check this insect? 

 As already suggested, in the general discussion, this is a sucking 

 insect and must be killed by a contact poison; that is every 

 insect must be hit to be killed. When we remember how well 

 they are protected and how rapidly they increase, the difficulty 

 of controlling them may be realized. It is realized still more 

 fully after we have tried to fight them. Nothing but the 

 most thorough treatment will be effective, for if only a few 

 individuals are left after a spraying they will increase so 

 rapidly that in a very few days things are as bad as ever. 



The best time to fight the aphis is in the early stages, before 

 the leaves have become much curled. Indeed, if some treatment 

 could be devised to destroy the eggs in winter, that would be 

 the ideal method. It has often been suggested that the winter 

 spraying with oil or lime-sulfur might be effective, but there is 

 much doubt in regard to this. Orchards which had been sprayed 

 every year for four years with both oil and lime-sulfur were 

 as badly infected with aphis as the most neglected orchard in 

 the neighborhood. 



The best treatment seems to be to spray with lime-sulfur at 

 the rate of one gallon of the commercial preparation to about 

 25 of water just as the buds are breaking and after the aphids 

 have hatched. If the right time can be selected after all the 

 aphids are hatched and before the leaves are out enough to be 

 damaged, and if the work is done thoroughly enough to de- 

 stroy this first generation, then there will be no future genera- 

 tions. Later treatment, when needed, must consist in using 

 some one of the contact sprays, either as a separate spray or 

 combined with the arsenical sprays which are given for codling 

 moth. On the Pacific coast, where these insects are troublesome 

 and where there is a form which does not curl the leaves, it is 

 the usual custom to combine a tobacco preparation with the 

 poison and the fungicide of the" regular sprayings and thus kill 

 both types of insects and the fungous diseases. 



