New York Agricultural Experiment Station. 391 



into starch, sugar or other compounds which the plant may 

 either appropriate for immediate needs or store away for future 

 use. The leaves may properly be called the food factory of the 

 tree. Is it not wisdom to protect this factory, so far as prac- 

 ticable, from all attacks of insects or diseases, that it may do its 

 work perfectly, and so enable the tree to yield an abundance of 

 fruit of the highest possible excellence? 



Experiments of 1895. 



Objects. — The objects of the experiments of 1895 in preventing 

 plum leaf -blight were to learn : 



(1) The comparative value of Bordeaux mixture and eau celeste 

 soap mixture for this purpose; . , 



(2) What is the fewest number of treatments necessary for 

 controlling this disease; 



(3) When is the best time for making the treatments. 

 Messrs. T. C. Maxwell & Bros, kindly offered one of their plum 



orchards, near Geneva, N. Y., for the use of the Station in these 

 experiments, and it is a pleasure to acknowledge their coopera- 

 tion and uniform courtesy. 



Plan of Experiments. — A block of 567 trees was selected for this 

 purpose. The varieties included in this block were Italian 

 Prune, (juii, Lombard, Purple Egg and Bavay's Green Gage, 

 familiarly known here as Reine Claude. One-third of the trees 

 of each variety were treated with Bordeaux mixture, as explained 

 hereafter, one-third were similarly treated with eau celeste soap 

 mixture and one-third were left untreated for comparison. 



The experiments were planned so that with each of these varie- 

 ties the trees that were sprayed with the Bordeaux mixture may 

 be compared with others of the same variety that were sprayed 

 with the eau celeste, and also with others of the same variety 

 that were left unsprayed. The accompanying plan shows the 

 location of the varieties with respect to each other and indicates 

 the treatment of each section. 



This plan included three series of treatments arranged so that 

 early and later treatments might be compared with each other. 



