42 



SPRAYING CROPS 



particles of poison rather evenly distributed over all 

 the exposed surfaces. 



There are exceptions, however, to this general 

 statement. The one most notable is the case of spray- 

 ing for the codling moth. Our present knowledge 

 regarding this insect has already been summarized 

 on page 2. As there stated, it seems especially 

 desirable in fighting this pest to be sure to lodge some 

 particles of poison inside the calyx of the young fruit. 

 Apparently this is not so well accomplished by a mist- 

 like spray as by one more coarse. Consequently it is 

 generally recommended that in spraying for the cod- 

 ling moth a spray be used that may be readily directed 

 against the young fruit, forcing good-sized drops to 

 lodge in the calyx so that on evaporation they will 

 leave behind a sufficient residue of poison to insure 

 the destruction of the young worms when they attempt 

 to enter the fruit. 



Amount of Spray to Apply — In general, spraying 

 is to be carried simply to a point where foliage and 

 fruit are thoroughly moistened. As soon as leaves 

 begin to drip it is time to stop, for if the application 

 is continued the globules of liqtiid will run together, 

 leaving on evaporation an excess of material on some 

 parts and not enough on others. 



On this phase of the subject. Professor L. H. 

 Bailey's advice is to ''spray thoroughly or not at all.'' 

 And he adds: 'T should say that fully half the 

 spraying which I have seen in western New York the 

 last two years is a waste of time and material. 

 Squirting a few quarts of w^ater at a tree as you hurry 

 past it, is not spraying. A tree is thoroughly and 

 honestly sprayed when it is zvct all over, on all the 

 branches and on both sides of all the leaves. An 

 insect or a fungus is not killed until the poison is 

 placed where the pest is. Bugs do not search for 



