APRIL, 1918 CIRCULAR No. 66 



AGRICULTURAL EXPERIMENT STATION 



KANSAS STATE AGRICULTURAL COLLEGE 



DEPARTMENT OF ENTOMOLOGY 



Spraying Fruit Trees 



J. H. MERRILL 



Fruit trees are sprayed for two reasons to control plant 

 diseases and to prevent damage from insects. So infrequently, 

 however, trees suffer from one type of injury alone that most 

 of the sprays in actual use are combined from fungicides and 

 insecticides. 



The fungicides most commonly employed are bordeaux mix- 

 ture and some forms of the lime-sulphur compounds. Bordeaux 

 mixture is decidedly the most efficient of all the fungicides, but 

 since its use during rainy weather is almost certain to cause 

 injury to both fruit and foliage, the lime-sulphur sprays are 

 often substituted. There are many diseases, however, such 

 as apple blotch and bitter rot, which cannot be controlled by 

 lime-sulphur, while in hot weather bordeaux mixture is much 

 safer. Hence the most satisfactory spraying method involves 

 the use of the lime-sulphur compounds in the early season, 

 when they are absolutely safe and will control any disease that 

 may appear at that time, while the bordeaux mixture is ap- 

 plied later, when it is safer on account of the heat and most 

 effective foe the later appearing diseases. 



THE LIME-SULPHUR SPRAYS 



The lime-sulphur sprays may be prepared at home or some 

 of the commercial brands may be used. Unless the grower has 

 a large number of trees to be sprayed, it will not pay him to 

 make the home-made solution, as the cost of securing the 

 equipment and of purchasing the ingredients in small quanti- 

 ties would be prohibitive. Not only is the task of preparation 

 very disagreeable, but unless directions are most carefully fol- 

 lowed, failure will probably result. Since the commercial 

 sprays are made in large quantities and with improved equip- 



