EXPERIMENTAL SPRAYING AT HIGH MOOR FARM. 93 



mixing together definite quantities of lime, sulphur and water 

 and then boiling for some time with artificial heat. 



Mention has already been made of the earlier experiments of 

 the writer with this material at Orono. There self-boiled lime- 

 sulphur made with hot water was more effective in scab con- 

 trol than that made with cold water where the slaking lime 

 provided the only source of heat to bring about chemical ac- 

 tion between the lime and the sulphur. Much better results 

 were secured with bordeaux mixture. 



Self-boiled lime-sulphur, also made with hot water, was used 

 at Highmoor but one season, or in the first series of experi- 

 ments. With it Mr. Bonns secured a reduction in the amount 

 of scab on the fruit from 41.75 per cent to 15.40 per cent as 

 compared with the check. That season however it gave nearly 

 as good scab control as did bordeaux mixture and home- 

 cooked lime-sulphur, but was considerably less efficient than 

 dilutions made from certain commercial brands of lime-sulphur 

 concentrate. 



Copper-lime-sulphur: Dr. Howard S. Reed and- his asso- 

 ciates in Virginia reported very satisfactory results in spraying 

 apple trees for rust, with lime-sulphur to which two pounds ot 

 copper sulphate dissolved in water were added to each 50 gal- 

 lons of dilute lime-sulphur spray. They stated that this spray 

 was not injurious to the foliage.* In a later publication addi- 

 tional data is given including the following statement. "On 

 most trees, when copper-lime-sulphur was used, it was possible 

 to find leaves whose margins were much darker green than 

 the normal leaves, but no evidence of scorching by this material 

 was found. "t The York Imperial is mentioned as the variety of 

 apples used. 



At Highmoor in 1914 a plot of Ben Davis was sprayed with 

 this copper-lime-sulphur mixture to which the usual amount 

 of dry arsenate of lead had been added. As far as scab con- 

 trol was concerned the results were practically identical with 



*Reed, Howard S., Cooley, J. S. and Crabill, C. H. Experiments on 

 the control of the cedar rust of apples. Bui. Va. Agr. Exp. Sta. 203. 

 Jan., 1914. 



tReed, Howard S. and Crabill, C. H. The cedar rust disease of 

 apples caused by Gymno sporangium juniperi-virginianae Schw. Tech. 

 Bui. Va. Agr. Exp. Sta. 9:87. May, 1915. 



