344 THE CULTIVATED EVERGREENS 



leaf -blade or the entire leaf. Small, irregular, dark brown spots 

 first, appear usually at the tip or round the margin of the leaf 

 and these, when the air is moist and warm, gradually increase 

 in size until the whole leaf is killed. Later the disease may 

 spread down the petioles and into the stems, killing the whole 

 plant. Badly infected leaves, petioles and stems become very 

 dry and brittle and such leaves drop off rather easily. It is 

 probable that the causal fungus {Phomopsis kalmiae) gains 

 entrance through wounds. 



All diseased portions of the plant should be carefully re- 

 moved and destroyed. This should include the cleaning up of 

 all fallen leaves. The young growth may be protected by the 

 use of bordeaux mixture. 



Diseases of azalea. 



The leaves of azalea and certain closely related plants are 

 commonly attacked by species of Exobasidium which cause 

 gall-like swellings. From Europe the disease has been reported 

 on the cultivated Azalea indica and A. pontica. It has been 

 recommended that all diseased parts should be cut out and 

 destroyed and the young growth sprayed with bordeaux mix- 

 ture or lime-sulfur. 



Septoria leaf-spot also occurs upon Azalea indica and is 

 caused by the fungus Septoria azaleas. Small brown spots 

 appear on the leaves and upon these the fruit-bodies of the 

 fungus can be seen later as small black dots. No control has 

 been suggested, but cleaning up the old leaves and the use of 

 bordeaux mixture or lime-sulfur should prove satisfactory. 



Diseases of cherry-laurel. 



The same fungus (Sphcerotheca pannosa. Lev.) which causes 

 a mildew on the rose and peach has been found to attack the 

 cherry -laurel {Prunus Laurocerasus) . While not a serious 



