July, 1912.] FUNGICIDES IN THE APPLE ORCHARD. 



13 



The numbers of the plots indicate their relative position in the 

 orchard. The orchard sloped toward plot 1. It is evident that 

 lime-sulfur did little to hold the scab in check, even on plot 3 where 

 two applications were given. Both Bordeaux and lime-sulfur gave 

 satisfactory results on the leaf spot. The Bordeaux russeted the 

 fruit, but the injury in most cases was not sufficient to affect the 

 value of the barreled apples. The Bordeaux also spotted the foliage 

 badly. Similar but less severe injury to the leaves was produced by 

 the arsenite of lime and Paris green. 



Considering both disease control and freedom from injury the re- 

 sults were not very satisfactory on any of the plots. It is probable 

 that the showers that followed the sprayings were responsible for 

 the Bordeaux injury and that they at the same time washed off 

 enough lime-sulfur to render it inefficient. 



The work on fungicides and insecticides was continued the follow- 

 ing summer in the Marsh orchards. The first spraying was made 

 May 12, before the flower buds opened, and the second May 26, 

 after the blossoms had fallen. Xo insecticide was used in the first 

 spraying. The arsenite of lime was prepared as in the preceding 

 season. The commercial lime-sulfur was diluted in every case to a 

 specific gravity of 1.010 (a dilution of about 1 to 30). 



Plot 4 was sprayed with a copper sulphid mixture that was very 

 similar to that recommended by Waite*. It was prepared by ad- 

 ding li pounds of copper sulfate, dissolved in 10 gallons of water, to 

 a 10-10-40 self-boiled lime-sulfur solution. The addition of the 

 copper sulfate solution thus brought the lime-sulfur to the 10-10-50 

 formula, which has been previously described. 



Plot 5 was treated with an iron sulphid mixture which had been 

 reported upon very favorably by Waite *. It was prepared by 

 adding 3 pounds of iron sulfate, dissolved in 10 gallons of water, to 

 a 10-10-40 self-boiled lime-sulfur solution. 



* Waite. M. B. Experiments on the apple with some new and little known fungicides 

 Bur. Plant Ind. U. S. Dept. Agr. Cir. 5.8. 1910. 



