EXPERIMENT STATION BULLETINS. 



457 



EXPERIMENTS IN 1921. 



This work was continued and expanded in 1921. A series of experiments 

 was conducted with peaches and plums at Hart in the orchards of Geo. A. 

 Hawley and Son and at Fennville with peaches in the orchard of P. H. Broe. 



Experiment at Fennville. The five acre orchard of Mr. P. H. Broe was 

 used for this season. It contains approximately five hundred mature trees, 

 and is about equally divided into two blocks, one of Elberta and one of 

 Salway. The orchard was one of the very few in the Fennville district which 

 was not seriously injured by the late freezes. The trees of both varieties 

 bore uniformly full crops; in fact, they set so much fruit that severe thinning 

 was necessary. 



Object of the experiment. This work was planned to determine whether 

 sulphur dust would control curculio, peach scab and brown rot (which 

 develops before harvest). The effect of sulphur dust on the foliage and the 

 color of the fruit was also to be considered. A "holding test", to determine 

 the effect of the dust upon the development of brown rot after harvest, was 

 made with Salway. 



Materials Used. The only material used was sulphur dust, no spraying 

 of any kind being done during the summer. The entire orchard was dusted 

 except three cross rows along the south end of the orchard which included 

 trees of both Salway and Elberta. The dust used for the early application 

 contained lead arsenate and was made up in the proportion of: 75 per cent 

 dusting sulphur, 15 per cent hydrated lime, 10 per cent lead arsenate. 



Fig. u. — ?ruit from dusted trees sUowing alfnpgt coigplete control of browu tot and peacb scab. 



