10 LIME-SULPHUE PREPARATIONS FOE APPLE DISEASES. 



Ill this experiment the conipaiative effect of tlie different mixtures 

 on the codhng moth was determined, and, as shown in Table I, the com- 

 bination of lime-sulphur and arsenate of lead controlled this insect 

 about as well as Bordeaux mixture and arsenate of lead. It seems, 

 therefore, that the poisonous action of this arsenical is not reduced 

 ])Y combining it with the lime-sulphur preparation. 



THE EFFECT OF THE SPRAYS ON THE FRUIT. 



In all the orchards treated the fruit sprayed with the several lime- 

 sulphur mixtures was smoother and more highly colored than that 

 sprayed with Bordeaux mixture. The Bordeaux mixture russeted 

 the fruit of the Ben Davis so that it did not have the "finish" required 

 for fancy apples, and a small percentage of it had to be dis- 

 carded as culls on account of the roughened appearance due to the 

 mixture. The Yellow Newtowns were russeted considerably and the 

 Winesaps only slightly, while the York Imperials showed practically 

 no russet effect. 



The lime-sulphur preparations caused no russeting, or at most 

 very little where the strongest solutions were used, and the fruit 

 sprayed with these mixtures was smooth, clean, and well colored. 

 The difference in color between the fruit sprayed with the Bordeaux 

 and that sprayed with the several lime-sulphur preparations was 

 very striking, and this feature alone would make the latter sprays 

 preferable to the former if other things were equal. 



EXPERIMENTS IN MICHIGAN. 



Experiments similar to those in Virginia were conducted at Douglas, 

 Mich., in cooperation with the Bureau of Entomology, and the results 

 were much the same. The w^ork was done by Mr. R. W. Braucher 

 under the writer's direction in the orchard of Mr. C. W. Gaylord. 

 The trees were sprayed just before they bloomed (May 19 and 20), 

 as soon as the petals fell (June 1 and 2), three weeks later (June 23 

 and 24), and ten weeks after the petals fell (August 10 and 11). 



There were six plats of from 13 to 20 trees each, including the 

 Wagener, Baldwin, Rhode Island, Roxbury, and Ben Davis varieties. 

 The commercial hme-sulphur solution, diluted to contain 2 gallons 

 to 50 gallons of water, without any arsenical, was applied to plat 1 ; 

 the same solution, with the addition of 6 ounces of Paris green, 

 was applied to plat 2; and the same solution, with the addition of 

 2 pounds of arsenate of lead, was used on plat 3. Plat 4 was sprayed 

 with self-boiled lime-sulphur (10-10-50) and 2 pounds of arsenate 

 of lead, and plat 5 was sprayed with 3-4-50 Bordeaux mixture 

 and 2 pounds of arsenate of lead, while plat 6 was left unsprayed. 

 The plats sprayed with the commercial lime-sulphur solution, espe- 



[Cir. 54] 



