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how it is that the poisons injure the peach, if injury is greater 

 at certain seasons of growth, if the time of day, meteorolog- 

 ical conditions, methods of application, and other minor con- 

 ditions, influence the results. It has been supposed by many that 

 the unusual meteorological conditions of last year were largely 

 responsible for the injuries. We performed experiments looking 

 in these directions last year, but desired the experience of a sec- 

 ond season to test the subject more fully. We now find that the 

 experiences of the two seasons coincide, so far as the experiments 

 are comparable. 



i. Our first trial this year was made May 21st, upon a block of 

 48 old peach trees. The first leaves at the time were scarcely 

 half grown. Both Paris green and London purple, ranging in 

 strength from one pound to 256 gallons, to one pound to 496 gal- 

 lons, were used. The results of this test were obscured by a 

 severe attack of curl -leaf, but injury was certainly very slight, 

 if any. 



2. May 31st, fourteen young peach trees of several varieties, in 

 another orchard, were sprayed, and also a number of trees of Rus- 

 sian apricots and Primus Si'moni, with one pound of London pur- 

 ple to 256 gallons of water. These trees were much farther ad- 

 vanced than those in the first lot. The peach leaves were much 

 injured, and they began to fall in about sixteen days. It was 

 noticed that the poison did not injure the tip leaves, but all those 

 which were fully grown at the time of spraying were killed, and 

 they fell off. Yet, to a casual observer, no injury was apparent 

 because the rapid new growth obscured it. The apricots and 

 Pr unns Simo7ii were not injured. 



3. Thirty large peach trees were sprayed June 2d, both London 

 purple and Paris green being used, in the proportion of one pound 

 to 200 gallons, and one pound to 256 gallons. These trees were 

 more backward in size of leaves than those in lot 2. The trees 

 treated with the two London purple mixtures were about equally 

 injured. Most of the leaves which were full grown when the 

 poison was applied fell off. About three weeks afterwards the 

 leaves were still falling, yet the shoots were growing so rapidly 

 that not more than ten per cent, of the total foliage of the tree at 

 this time was injured. None of the shoots were injured. A very 

 trifling and unimportant injury resulted from the stronger Paris 

 green mixture (1 lb. to 200 gals.), but none from the weaker one. 



