DUSTING AND SPRAYING EXPERIMENTS OF 1918 AND 1919. 



:u 



It developed steadily until by September 1 the trees were practically 

 defoliated. 



On <ltix(c<l trees the disease was evident early in August and by the 

 middle of September many of the trees were badly defoliated. 



*l>ni!i<>d trees showed no evidence of leaf-blight until late in Septem- 

 ber and then the development was only very slight. 



ConlotJii/riu-m on Cherries. When the fruit was being harvested it was 

 noticed that many Morello cherries were drying up and hanging onto 

 the trees. Some had nothing left but the pit covered with the dry 

 cherry skin; some were partly dry and others were in just a slightly 

 wrinkled condition. It was found that around the base of the stem of 

 all atl'ected fruits there was a cankered area which apparently had 

 girdled the stem so that the sap supply was shut off. None of this 

 trouble was found on Montmorency trees. 



FIG. 13. CONIOTHYRIUM ON SOTH CHKHUY. A small branch from tin English Morello 

 tree afTcctt-d by ( 'oniot li.vrinm. Photo July 1">, 191!). 



All the all'ected cherries hung tightly to the tree throughout the sum- 

 mer and were still there in December. 



The trouble was found to be caused by a species of < oniothyrium and 

 might have come from a planting of black raspberries which stood just 

 south of the cherry orchard. 



There was considerable cane blight in the berries which is caused 

 by a fungus known as Coniothyrhim Fuckelii.* 



Control of Coniotlnjnnm- on Clicrricx. All trees in the dusted plot 

 which bore fruit had cherries all'ected by this trouble. No affected 



*The fungus on the cherries was identified by Ray Nelson of the Botanical Department. 



