74 ORCHAKD CATERPILLARS. 



Grounds, writing to me on the 3rd of July, 1890, and mentioning his 

 satisfaction with the results of spraying, also noted, ' The proportions 

 I fixed upon after the first trials, viz., 1 oz. to 10 gallons of water 

 for Plums, and 1 oz. to 20 gallons of water for Apples, must not be 

 exceeded.' 



" 'Insist upon the mixture not being made too strong ; 1 lb. to 200 

 gallons I find very useful, and I never use stronger than 1 lb. to 120 

 gallons.' — (J. F.). Advice sent by the Entomologist of the Dominion 

 of Canada." 



Dijficulty 2nd. " 1 jind that even when the Paris-green is used in the 

 proportion of 1 oz. to 10 gallons of water, unless the cjierator is judicious 

 and careful, the foliage of the trees tcill get injured. This would arise from 

 the particles of the Paris-green settling at the bottom of the vessel dunng the 

 time it is being applied, so that the effect in such case ivould be that one por- 

 tion of the solution is too weak to accomplish any object, and the portion 

 at the bottom of tlie vessel would be disproportionately strong and dangerous. 

 So that care should be used in p>utting solution in general commotion every 

 few minutes, so as to avoid the Paris-green settling.'' 



DIRECTIONS. — "In application of Paris-green sprayings, it must 

 always be borne in mind that, whatever kind of engine or spraying 

 machine is used, the mixture must be kept an even strength through- 

 out, and no sediment allowed to form at the bottom, or damage to 

 the leafage is sure to happen. 



" On these points Mr. Fletcher, the Dominion Entomologist of 

 Canada, wrote to me as follows, and also enforcing care as to over- 

 application : — 



'''Paris-green. — You are quite safe in recommending this; but 

 insist upon these two things, viz., 1st, to keep the mixture (which is a 

 mixture, not a solution) well stirred all the time, and have the barrel 

 well washed out after it has been filled ten or twelve times. The 

 Paris-green is very heavy, and will keep sinking to the bottom unless 

 constantly agitated ; and as the barrel is frequently re-filled the 

 residue will keep accumulating, until it will be too strong as the 

 mixture reaches the bottom.' " 



Difficulty Srd. " Another danger arises from the operator, Istly, put- 

 ting on the solution too topiously. Great care should be used in securing 

 the best sprayer ; the * Eclair' I have found the best. 2ndly, to be careful 

 that the foliage of the trees is only bedewed or well-misted. If a quart of the 

 fluid is used in suffusing a tree when a pint would be adequate to destroy 

 caterpillar -life, your excessive quantity of fluid used would be equivalent to 

 the using of an extra quantity of Paris-green." 



DIRECTIONS. — " With regard to method of application of the 

 spray. This should be thrown so finely as to reach all parts of the 

 tree and both sides of the leaves, and coat the leaves as with a fine 



