APPENDIX. . 303 



reported captures of the insect in large numbers at baits or traps are the 

 results of mistaken identity.* 



There is one suggestion of considerable importance to be made in this 

 connection. As many of the worms are carried with the fruit into the store- 

 rooms in the fall, where they spin their cocoons, consequently the moths 

 often emerge in the spring in considerable numbers and escape through the 

 windows and doors. It would be a simple matter to put screens or mosquito 

 netting over all openings during May, .Tune, and July, thus effectually trap- 

 ping the moths which would otherwise find their way to orchards and start 

 a numerous progeny. The number of moths which sometimes emerge in 

 these fruitrooms i*; surprising. Hundreds of cocoons have been found in a 

 single apple barrel, and in one instance in California the openings in a fruit- 

 room were screened and nearly sixteen thousand codling moths were thus 

 trapped and killed between the middle of April and the end of August, 

 nearly one thousand being caught in a single day, June 1"). It would not be 

 necessary to go to the trouble of catching all the moths in a room thus 

 screened, for they would soon die a natural death. 



CAN WE KILL THE EGGS V 



It is only recently that anyone has suggested the possibility of reaching 

 the codling moth in its egg stage. Mr. Card reported from Nebraska in 

 August, 1897, that "the eggs are very easily accessible, being laid as they 

 are on the upper surface of the leaf. In a limited way, in laboratory 

 experiments we have found that kerosene emulsion will destroy these, but 

 we are not yet able to say whether a strength that may be safely used will 

 prove effective in field work.'* Mr. Washburn seems to have been the only 

 one to try any other experiments against the eggs. In 1892 he allowed a 

 few apples, upon which eggs occurred, to remain in a solution of one pound 

 of IXL ( a mixture of lime, salt, and sulphur ) about one pound of whale-oil 

 .soap, and about an ounce of paris green, in sixteen gallons of water ; sub- 

 sequently these eggs hatched. 



Apple trees have been sprayed with similar substances. In 1878 Cook 

 sprayed an apple tree weekly from May 15 till the last of .June with a strong 

 solution of soft soap, with the results that not a single apple was wormy, 

 while an unsprayed tree had nearly three-fourths of its fruit infested. 

 Whether the strong smell of the soap kept the moths away, whether the 

 eggs were killed, or how the solution affected the insect, is not suggested. 

 Gott' has sprayed apple trees with kerosene emulsion once (June 11), and 

 with McDougall's sheep dip twice (May 25 and 30j, but with little or no 

 effect on the codling moth. 



It may be possible to reach the eggs with a spray in Nebraska, where they 

 seem to be laid on the leaves, but our experience in trying to kill the eggs 

 of insects leads us to fear that it will take a stronger mixture than the plant 



♦The use of baits has recently received considerable attention in Germany, and in 

 Der Praktiiche R'ltgeber, for 1895, is recorded an account of an experiment with glasses 

 of apple jelly hung in the trees. We glean from the report that quite a number of cod- 

 ling moths were thus captured, about half of them being females. 



