22 ACRICLT/rURlC OF MAINIJ. 



early, since these remedies are preventives, not cures, and their 

 use must precede the diseases they are directed against. The 

 mixture as we use it consists of 5 pounds each of copper sulphate 

 and Hme with ^ pound Paris green per barrel of 50 gallons of 

 water. Where applied thoroughly and in season this combina- 

 tion has proved almost a cure-all for potato maladies. During 15 

 years past we have not once failed, by two or at least three appli- 

 cations of it, to carry our vigorous main crop varieties to full 

 maturity practically free from disease. The following shows the 

 gain as compared with the use of Paris green alone. 



GAINS FROM THE USE OF BORDEAUX MIXTURE. 



(Potatoes usually planted about the middle of !May, sprayed 

 in July and August.) 



No. yiel<l where Where not 

 Variety. sprayings, sprayed. sprayeri. Gain. 



White Star 



While star 



Wnite Star 



White Star ... 



White star 



Polaris 



Polaris 



White star 



Average 3 varieties 



Delaware 



Delaware 



Delaware 



Green Mt 



Delaware 



Delaware 



•295 ITfi Hit 



This gain has in part come from checking the rot. but the 

 important thing to note is that the greater portion of it is due to 

 prolonging the healthy life of the leaves into the autumn as was 

 shown by the earlier table en the time and rate of development. 

 If even a single week is added to the vigorous life of the plants 

 the gain will pay for the spraying, and if four weeks are added, 

 as has resulted several times, the crop is doubled. 



There are a number of practical questions yet unanswered. 

 Space does not permit their discussion in detail. We will merely 

 summarize our conclusions regarding them. 



