1322 The Vegetable IxnrsTKv i.\ Xew York State 



a plant is decidedly more free from disease than its neighbors, 

 save seed from it and try it ont the next year. Plant different 

 varieties and examine for differences in disease resistance. 



Spraying. Many blight and dead spot diseases can be controlled 

 by applying some material which is destructive to the causal 

 parasite but harmless to the crop. For perfect control all sus- 

 ceptible parts must be kept coated with the spray material in 

 order to prevent entrance of the parasite, for once entrance has 

 been gained spraying is useless. Spray before rains, not after, 

 for the parasite requires moisture to gain entrance to a plant, and 

 well-made spray mixtures do not wash off. Bordeaux is the stand- 

 ard material for vegetable spraying. For fruits lime-sulphur 

 has largely taken the place of bordeaux, but it has in no case been 

 sufficiently tested on vegetables to warrant its substitution for 

 bordeaux. Careful tests have shown that in some cases lime- 

 sulphur actually checks the growth of vegetables. 



Bordeaux, 5-5-50, which is the formula usually used, consists 

 of 5 pounds copper sulphate, 5 pounds high-grade stone lime and 

 50 gallons water. The copper sulphate is dissolved by suspend- 

 ing in a sack in the top of a few gallons of water in a wooden 

 vessel. The stone lime is slaked in a separate vessel by adding 

 water a little at a time. Both are then diluted to 25 gallons and 

 poured together in this diluted condition. After thorough stirring 

 the mixture is ready for use. Fresh hydrated lime may be used 

 in place of the stone lime. If there is any doubt about the lime 

 being high-grade and fresh, get an ounce of yellow prussiate of 

 potash at a drug store, dissolve it in a pint of water, and add a 

 few drops to the well stirred bordeaux. If the solution shows no 

 change in color the bordeaux is all right, but if it turns dark 

 brown as soon as it strikes the bordeaux, the lime was either 

 low-grade or air-slaked, and the bordeaux will burn foliage if 

 used. Add lime from a fresh supply until the prussiate solution 

 does not change color. 



Where smooth glossy plants like asparagus are sprayed, it is 

 advisable to use a sticker with the bordeaux. Boil 2 pounds 

 resin, 1 pound sal soda crystals and 1 gallon water in an iron 

 kettle until clear, which requires one to one and one-half hours. 

 Add this to 50 to 100 gallons of bordeaux. 



