198 STATE BOARD OF AGRICULTURE. 



growers to use commercial fertilizers, but to direct them as to the kinds of 

 fertilizers that will give the best results and the amounts that should be used. 

 As in the past the work of Mr. W. C. Button has been largely along the 

 lines of spraying and dusting. Laboratory studies were made during the 

 winter months on the various brands of spray materials offered on the market, 

 together with their physical characteristics. Studies were made on the use 

 and value of spreaders in sprays, and field tests of spreaders are being made the 

 present season. A brief summary of the results of the work along spraying 

 lines for the season of 1920 follows : 



Dusting and spraying apples. — Sulphur dust gave as good control of apple 

 scab and codling moth as standard liquid sprays. Variety: Grimes golden, 

 location: South Haven. 



Dusting and spraying pears. — Two orchards of Bartlett: location, South 

 Haven. The average results in two orchards were about equal for scab con- 

 trol. Physical condition of dusted foliage much superior to that sprayed with 

 lime-sulphur 1 to 40 or 1 to 50. An extra application (pre-pink) was of value 

 in controlling scab. This application probabl}^ is very desirable where scab 

 is prevalent. 



Copper sulphate dusts. — (Sanders dust) did not give satisfactory control of 

 scab on either apples or pears. Location: South Haven. 



Peach dusting and spraying. — Dusting for leaf curl Avith soluble sulphur 

 and Bordeaux dusts did not give satisfactory results. Results consistent 

 with those of 1919. 



Summer dusting of peaches devoid of definite results because of absence 

 of injury on checks. 90-10 and 80-10-10 sulphur-lead dusts were entirely 

 safe on peach foliage. Copper sulphate dust was also safe. Location: 

 Saugatuck. 



Plum dusting and spraying.— 'EmphsLsHs on rot control. Lombard variety; 

 checks very bad; fruit nearly total loss on some trees. Dusted and sprayed 

 apparently equal at harvest with very little rot on either. Sprayed trees 

 received last application of lime-sulphur (1-40) about one month before har- 

 vest. Sulphur dust (straight sulphur), applied then, also one week before 

 harvest. Holding quality of dusted fruit decidedly best. Location: South 

 Haven. 



Dry lime sulphur on duchess apples. — Results were consistent with those of 

 previous year. Dry lime sulphur regardless of strength used did not give 

 results equal to lime-sulphur solution (1 to 40) although no definite plots 

 were arranged on this point, the results indicate very strongly that a pre- 

 pink application is desirable to prevent an early infection of scab which fre- 

 quently occurs on duchess. Location: South Haven and Grand Rapids. 



Cherry dusting and spraying.- — Location: Traverse City ; varieties : English 

 Morello and Montmorency. Lime-sulphur, 1 to 40, Bordeaux 4-4-50, sul- 

 phur dust and copper sulphate. Injury on Montmorency checks not severe 

 but control with all materials was satisfactory. There were some slight 

 differences. On Morello, checks practically defoliated. Very little leaf 

 spot on Bordeaux, a little on lime-sulphur plot, more on sulphur dust plot 

 and still more on copper sulphate dust plot. 



Considerable injury on foliage of both varieties developed from the use of 

 Bordeaux. The results indicated that lime-sulphur should be used at the 

 rate of one and one-half gallons to 50 to give best control. 



