ORNAMENTAL PLANTS 473 



Botryose (Botrytis vulgaris Fr.). — This occurs upon leaves 

 and flowers much as upon lettuce. 



Bordeaux mixture is useful with all of these Primrose 

 diseases. 



PRIVET 



Gloeosporiose, anthracnose (Gloeosporium cingulatum ^ 

 Atk.)- — Twig blight superficially resembling that of the 

 pear is a character of this disease in its later stages, terminal 

 parts of the twigs 2-5 cm. long being affected. The line of 

 separation between diseased and healthy tissue is a sharp 

 one through shrinking and depression of the diseased part. 

 In early stages depressed oblong diseased spots, at first very 

 minute, are seen upon the bark. These spots enlarge, 

 eventually girdle the twig, and cause the death of the distal 

 part. Minute black elevated acervuli, idsible to the naked 

 eye, are scattered over the surface of the original disease 

 spots. 



Affected branches should be cut well below the disease 

 and burned. A spring spraying, before the buds swell, 

 with any good dormant spray will still further reduce infec- 

 tion. 



ROSE 



Black spot (Actinonema Rosce (Lib.) Fr.). — Both in and 

 out of doors, this is a widely known and destructive rose 

 disease. It was first described in 1826, and is now known 

 throughout Europe and the United States. It consists of 

 irregular circular or oval indefinitely bordered black spots 

 upon the upper surface of the leaves that are mature or 

 ' Atkinson, G. F., N.Y. (Cornell) Agr. Exp. Sta. Bui. 49. 



