PEACH SCAB AND ITS CONTEOL. 47 



While many other spraying experiments were reported during this 

 period and subsequently, no material advance was made until Scott 

 (1907 and 1908), realizing that the copper sprays in their present 

 state of development are too toxic for general application upon peach 

 fohage, sought to develop an efficient fungicide which would be appli- 

 cable to tender-foliaged plants without serious host injury. He con- 

 ducted prehminary experiments with self-boiled lime-sulphur and 

 reported very promising results in the control of peach scab. The 

 same author (1909, p. 7-12) carried out further similar experiments 

 and recommended (p. 11-12) self-boiled lime-sulphur treatments for 

 the control of this malady. Scott and Ayres (1910) and Scott and 

 Quaintance (1911) confirmed these results by extensive spraying 

 experiments and gave detailed recommendations for the self-boiled 

 lime-sulphur treatments. 



Lewis (1910) conducted peach-spraying experiments in which he 

 used, comparatively, self-boiled lime-sulphur, home-boiled lime- 

 sulphur, Bordeaux mixture, and certain proprietary fungicides, each 

 preparation being applied alone and in combination with arsenate 

 of lead. He reports self-boiled lime-sulphur as giving the most 

 favorable results, his recommendations (p. 47) paralleling those of 

 Scott and Ayres (1910). 



Clinton and Britton (1911, p. 604-618) sprayed peaches with self- 

 boiled lime-sulphur, potassium sulphid, and certain proprietary 

 sprays. In certain applications, insecticides were added to the fungi- 

 cides. These authors report most satisfactory results from the self- 

 boiled lime-sulphur and recommend its use. 



Blake and Farley (1911, p. 11-30), in an extensive series of peach- 

 spraying experiments, made comparative tests of home-boiled lime- 

 sulphur, self-boiled lime-sulphur, and certain proprietary fungicides. 

 They regarded all the preparations used except self-boiled lime- 

 sulphur and a sulphur paste as too toxic to be applied with safety to 

 peach foliage unless made too dilute to be efficient. They recommend 

 the use of self -boiled lime-sulphur, which they state (p. 26) "is the 

 best fungicide known at the present time for the control of peach scab 

 and brown-rot." 



Norton and Symons (1912, p. 266-268), in continuation of pre- 

 vious experiments, tested self-boiled lime-sulphur and various pro- 

 prietary preparations in peach-scab control. They reported that 

 self-boiled lime-sulphur gave the most favorable results. 



These and like experiments appear to show (1) that Bordeaux mix- 

 ture and various other copper sprays, lime-sulphur, and liver of sul- 

 phur, in combination with arsenate of lead, in concentrations suffi- 

 ciently strong to control scab, are too toxic to be appHed generally as 

 summer sprays for the peach; (2) that peach scab may be controlled 

 by spraying with self-boiled lime-sulphur, alone or mixed with arse- 



