DUSTING AND SPRAYING EXPERIMENTS OF 1918 AND 1919. 37 



EXPERIMENTS WITH CURRANTS 



DUSTING AND SPRAYING EXPERIMENTS WITH CURRANTS 



The planting of currants on the Horticultural grounds at East Lan- 

 sing was used for a test of several fungicides and insecticides. There 

 were two sections of this experiment. One was a comparison of dilute 

 lime-sulphur, bordeaux and sulphur dusts for the control of anthrac- 

 nose. Anthracnose is caused by a fungus known as Pseudopeziza Ribis. 

 It usually occurs as a leaf-spot. Another leaf-spot known as Septoria 

 leaf-spot is sometimes found and can be controlled by the treatment 

 recommended for anthracnose. The other part of the work was a test 

 of lead arsenate, calcium arsenate and magnesium arsenate, to deter- 

 mine if any of them would cause foliage injury. 



This planting contains bushes of several varieties and the experi- 

 mental plots were arranged so that all varieties would be included in 

 each plot. The arrangement of the plots is shown in Chart VIII. 



Mah 'rials. The treatment given each plot is shown here. 



Plot 1. Dusted. 90-10 mixture and straight sulphur. 



Plot 2. Sprayed. Bordeaux. 44-50. Lead arsenate was used when 

 necessary. 



Plot 3. Sprayed. Lime-sulphur, 1 to 40 and Corona dry lead 

 arsenate, 1 Ib. in 50 gal. This plot was included in both 

 sections of the work. 



Plot 4. Sprayed. Lime-sulphur, 1 to 40, and Dow magnesium 

 arsenate, 1 Ib. in 50 gal. 



Plot 5. Check. Unsprayed. 



Plot 6. Sprayed. Lime-sulphur, 1 to 40 and Corona calcium arse- 

 nate, % Ib. in 50 gal., plus 3 Ibs. hydra ted lime. 



