46 PLANT DISEASES 



good account of the parasites the land contains, and 

 produce excellent results in the crop. Half the amount 

 of this mixture suffices on ordinary land, and is just as 

 good for tomatoes as for potatoes.' Journ. Hort. and 

 Cott. Gardener^ July 25, 1895. 



The above is introduced for the reason that when applied 

 to tomatoes, the crop invariably remained untouched by 

 fungous parasites. 



POISONOUS PROPERTIES OF FUNGICIDES 



From time to time the serious question as to the 

 advisability of using fungicides, more especially Bordeaux 

 mixture, on account of their poisonous properties, has 

 been discussed, and the tone at one time assumed seemed 

 likely to deal a death-blow to their use. 



The two leading points in the discussion were: (i) 

 danger to human life by partaking of fruit sprayed with 

 Bordeaux mixture; and (2) injury to the soil caused by 

 the constant application of the same solution. 



The subject has been investigated, either directly or 

 indirectly, by leading European and American chemists, 

 and the verdict is that there is no risk whatever in par- 

 taking of fruit that has been sprayed, provided the pre- 

 cautions given below are observed, and that the soil is 

 in no way injured by the quantity of the mixture it 

 receives. 



The important points to be kept in view in spraying 

 fruit with Bordeaux mixture are, to decrease the strength 

 of the solution as the fruit approaches maturity, and to 

 cease spraying altogether some little time before the 

 fruit is fully ripe. Lettuce and similar crops that mature 



