252 Diseases of Greenhouse Crops 



Leaf Spot 



Caused by Phyllosticta drac(zncz Griff, and Maubl. 



Symptoms, This trouble is manifested as minute, 

 irregular pale spots and bordered by a narrow, 

 brown colored elevated band. The pycnidia are 

 not always present on the spots until the leaves 

 fall off. The spores ooze out as whitish tendrils. 

 This form of spot was first described by Griffon 

 and Maublanc * on greenhouse dracense in France. 

 Its extent in the United States is as yet little known. 



Leaf Blotch 



Caused by V ermicularia concentrica Sev. 



The thicker-leaved sorts such as Dracena goldiena 

 and the variegated D. Lindemi are often subject 

 to a blotch disease. The trouble is characterized by 

 large, brown blotches on the leaves. Very little 

 is known of the causal organism. Spraying with 

 Bordeaux or any other colorless fungicide may con- 

 trol the disease. 



Daffodils 

 Cultural Considerations^ see Tulips, p. 348. 



Diseases of the Daffodil 



The Daffodil is a very hardy plant. It thrives 

 equally as well in the greenhouse as it does out of 

 doors. 



* GriflFon, M. M., and Maublanc, Bui. Soc. Mycol. de France 25 : 

 239, 1 9 10. 



