THE APPLE-TREE CASE-HEAPER : REMEDIES. 167 



plied to ten tluin to a thousand, and if it pays to employ remedial 

 measures on a small scale, it will, at the least, jirove equally profitable 

 on a larger scale. 



Ijondon purple would probably be quite as valuable in protecting 

 large orclnirds as the more costly Paris green. Its much less cost would 

 permit of its more thorough and frequent use, and it seems also to 

 possess the additional j'ecommendation of being absorbed to a greater 

 degree by the leaves. It could be conveniently applied by means of 

 the forcing pump (illustrated on pages 29 and 30), throwing the liquid 

 from a barrel placed on a wagon and drawn through the orchard. The 

 eflQcacy of this material in preventing the ravages of the Codling moth 

 of the apple has been tested by Professor A. J. Cook, and its use for 

 the purpose was strongly recommended by him, and sustained against 

 adverse criticisms, at the Cincinnati meeting of the American Asso- 

 ciation for the Advancement of Science. Young apple-trees which 

 had been treated by this method had given fine crops of sound fruit, 

 which had been freely eaten by himself and family without any in- 

 jurious results. The quantity of London purple used was a table- 

 spoonful to a pail of water, which was found to answer for three trees. 

 In using it against the case-bearer, a large amount of the liquid should 

 be thrown upon the tree, as it would need to be very generally dis- 

 tributed in order to reach all the buds or the foliage. 



As a general rule, the best time to attack our injurious insects is 

 when they are just from the egg, and so delicate. that they may be 

 easily destroyed. The young caterpillars of the case-bearer emerge 

 from the eggs during the month of September. It would not be pru- 

 dent to apply the poison at this time, except to trees bearing early 

 apples from which the fruit had been gathered. Even to these, it 

 would require a large amount of liquid to reach all the leaves of the 

 tree upon which the young larvae might be feeding. Beyond this, the 

 feeding done by them before retiring, less than half-groAvn, within 

 their cases for hibernation, would not be of any appreciable injury. 

 The proper time, therefore, to use the poison is wlien the larvae have 

 awakened from their winter's sleep, and are resorting to the buds to 

 resume their feeding. This can easily be ascertained by observation, 

 and careful inspection of the infested trees should be made during the 

 first warm days in early spring, as soon as the first insects are seen 

 upon the wing. If at this time, all the expanding buds be sprayed 

 with the liquid, and the operation be repeated two or three times at 

 intervals of a week or after rains, during the opening of the buds and 

 the unfolding of the leaves, very few of the case-bearers will be spared 

 to continue their ravages, and to complete their transformation to the 

 perfect moth, laden with eggs for the perpetuation of the pest in an- 

 other brood. 



