040 ANNUAL REPORT OF THE Off. Doc. 



Results of exporiments conducted in Arkansas by the Depart- 

 ment of Agriciillure were not favorable to llie lime-sulplmr solu- 

 tion in the control of bitter rot and apple blotch. These two dis- 

 eases were checked by the spray but not lhorouf>hly controlled 

 There is therefore some doubt as to the efficiency of the lime-sulphur 

 solution as a remedy for -bitter rot and blotch. 



In both the Virginia and the Michigan experiuuMits (he coiuuier- 

 cial lime-sulphur solution at a strength of 2 to .50 sliglitly scorclied 

 the leaves particularly on the terminal shoots, but this did not 

 prove to be serious and at the end of the season the foliage was 

 in good condition, tlu; ajtple leaf-spot having been controlled and 

 the cedar rust held in check. It was found also that arsenate of 

 lead used with the lime-sulphur solution did not result in injury to 

 fruit or foliage and that it controlled codling moth as thoroughly 

 as when combined with Bordeaux mixture. A full account of Ihese 

 exi)eriments was published in Circular No. 54 of the Bureau of 

 Plant Industry. 



EXPERIMENTS OF 1910 



During the past season experiments were conducted at Waynes- 

 boro, Virginia, on Winesap, York Imperial and Ben Davis. From 

 75 to 100 trees of each variety were sprayed and a check of about 

 ten trees of each variety was left unsprayed. Each variety was divid- 

 ed into four plots and treated as follow^s: 



Plot 1. — Commercial lime-sulphur solution, 1^ to 50 with 

 2 pounds arsenate of lead. 



Plot 2. — Home-made lime-sulphur solution, 2 pounds of 

 lime and 4 pounds of sulphur to 50 gallons of water, with 

 2 pounds arsenate of lead. 



Plot 3. — Bordeaux mixture, 3 pounds bluestone and 4 

 pounds lime to 50 gallons water, with 2 pounds arsenate 

 of lead. 



Plot 4. — Check, not sprayed. 



The Winesaps were sprayed, (1) after the cluster buds opened, 

 just before they bloomed (April 5th) ; (2) as soon as the petals 

 fell (April 19th) ; (3) three to four weeks later (May 17th) ; and 

 (4) nine weeks after the petals fell (June 26th). The Ben Davis 

 and York Imperial received only three treatments, the first applica- 

 tion given the Winesaps having been omitted from these varieties, 

 for the reason that in Virginia they do not suffer seriously from 

 attacks of scab. 



LIME-SULPHUR SOLUTION AND APPLE SCAB 



In order to find the comparative efficiency of the sulphur and 

 copper sprays for the control of apple scab, fruit from four Wine- 

 sap trees in each plot and six check trees were sorted and the re- 

 sults are given in the following table: 



