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April, '15] GLENN: APPLE FLEA-WEEVIL 285 



method of applying the spray so as to cover the under sides of the 

 leaves is at least moderately effective. 



In order to determine the proper time to spray, one has only to 

 recall the seasonal history of the species. The beetles feed upon the 

 leaves of the trees about two weeks before egg-laying begins to any 

 extent. Egg-laying begins shortly before the trees come into bloom, 

 and continues for about four weeks. Spraying should therefore be 

 begun before the trees are in bloom, in order to destroy the beetles 

 before eggs for the new generation are deposited. If spraying with 

 arsenicals is delayed until after the petals fall, a large proportion of 

 the eggs will have been deposited and no amount of spraying at this 

 time or later can prevent the development of the larvae and the final 

 emergence of the adults of the new generation. 



The adults of the new generation are to be found on the trees through- 

 out June, hence spraying to destroy these and so prevent them from 

 injuring the foliage should begin about the first week in June. 



Many orchard men do not use an arsenical spray before trees are 

 in bloom and hence, for this reason alone if for no other, spraying has 

 proven ineffective so far as the development of the new spring genera- 

 tion is concerned. 



It appears, therefore, that the apparent ineffectiveness of arsenical 

 sprays has been in a measure at least due to each of the four causes 

 above mentioned, and it seems very probable that by the observance 

 of the following suggestions satisfactory results will be secured: 1. 

 Increase the amount of arsenate of lead to 3 pounds of the paste to 

 100 gallons; 2. Omit the fungicide from the arsenical spray when spray- 

 ing to control the apple flea-weevil; 3. Spray with a pressure of 200 

 pounds or more, and direct the spray so as to cover the entire leaf 

 surface; and 4. Begin spraying while the fruit is in the cluster-bud 

 stage, spray again after the majority of the new generation of beetles 

 have emerged, and, if necessary, follow this spraying with another as 

 soon as possible. 



Contact Speays. — In the early experiments it was found that the 

 beetles are very easily killed with kerosene emulsion and nicotine sprays, 

 the only difficulty being in getting the spray on them in sufficient 

 quantities. To accomplish this two large canvases were made, each 

 15 by 30 feet. These were spread beneath the trees while they were 

 being sprayed. The spray was driven under a pressure of 200 pounds 

 or more to the square inch, and directed upward so as to strike the 

 under sides of the leaves. As soon as the spray strikes the leaves the 

 beetles fall to the canvas, where they are killed by the kerosene. A 

 5 per cent emulsion is fairly effective, but a 7 per cent emulsion works 

 much better. Black-leaf-40, at the rate of 1 pint to 100 gallons of 



