POTATO FLEA-BEIiTIv];. 47 



Remedies. The foregoing experiments with Bordeaux mix- 

 ture have only again demonstrated what has long been known 

 that this fungicide is an excellent flea-beetle repellant. As it is 

 not a poison but a rei)cllant the key note to success in its use 

 lies in thoroughness and frequency of spraying. Professor R. 

 L. Jones formerly of the Vermont Experiment Station was the 

 first to test this remedy anJ to demonstrate its efficiency. 



Although flea-beetles are sometimes abundant in fields which 

 are fairly well sprayed it must be borne in mind that the spray 

 rarely covers the whole leaf and that the beetles attack the un- 

 sprayed part. There is, however, another factor which enters 

 and that is that the beetles are much inclined to feed on the 

 .uiderside of the leaf frequently stopping just short of the 

 upper surface. The tissue above dries awa}^ and this leaves a 

 small hole through the leaf. As the spray for the most part 

 strikes onl}'- the upper surface its effectiveness as a repellant is 

 thus largely nullified. It is certain that bordeaux mixture 

 would be much more effective ii it could be applied to the under 

 surface of the leaves. A spraying apparatus so devised that a 

 portion of the spray could be directed upwards against the un- 

 derside of the leaves would do much towards lessening the dam- 

 age wrought by flea-beetles and thus also diminish the injury 

 caused by early blight. Director Chas. D. Woods, of this station 

 in a letter published Oct. 19, 1912, upon the subject of "Early 

 Blight and Flea beetles" closes with these words, ''One of the 

 projects of the Maine Agricultural Experiment Station for the 

 coming year is the construction of a more' efficient potato spray- 

 er and one with the nozzles so arranged, if possible, that they 

 will meet the necessary requirements in the manner of the ap- 

 plication of the spray to control early blight and flea-beetles. 

 This may mean, to secure sufficient pressure and volume of 

 spray, the construction of some sort of a gasoline power spray- 

 er for potatoes." 



From what has already been said it will be noted that the 

 most effective remeU^ yet known against flea-beetles is the use 

 of bordeaux mixture. It must be sprayed on so that the vines 

 are well coated, and repeated at frequent intervals, at the rate of 

 TOO or more gallons per acre. If other insects are also present, 

 two pounds of lead arsenate to 50 gallons of the bordeaux, may 

 be addcT 



