52 EXPERIMENT STATION. [Jan. 



cal as regards freedom from rust, one is likely to have it very 

 severely and tlie other not at all, which proves that the method 

 of handling the plant has everything to do with the occurrence 

 of the rust. When plants are grown outside, as they occasionally 

 are in summer, and are exposed to rains and dews, they are very 

 likely to become infected, but when grown inside, and especial 

 care given to watering the foliage, little rust is present. 



Powdery mildew (ErysipJie), although occasionally seen on 

 chrvsanthemum foliage, has never been considered a serious 

 trouble, and is seldom, if ever, severe enough to require treat- 

 ment. Stem rot, occasionally caused by Fusarium, which is 

 more likely to affect the weak stems on closely planted crops, is 

 sometimes destructive, but the chrysanthemum is, as a rule, 

 quite immune to stem rots. 



Caenations. 



The principal troubles peculiar to the carnation are the stem 

 rots, termed the wet and dry rot, and the rust. There are other 

 troubles which are not serious, however, such as leaf spot 

 (Septo7'ia), jiurple joint, stigminose, etc., the latter being caused 

 by insects. The breeding and selection of new varieties of car- 

 nations has had a more important influence on the elimination 

 of carnation diseases than anything else. Carnation rust, which 

 a few years ago gave much uneasiness among the growers, is now 

 fairly well handled by expert carnation men. Careful attention 

 given to syringing the plants has been of great value in pre- 

 venting the rust, as has also subirrigation, or applying the water 

 below the surface. 



The stem rots are more recent troubles and are more difficult 

 to handle. Wet rot, caused by a sterile fungus {Bhizodoiiia) 

 can be easily controlled by sterilizing the soil with steam, and 

 formalin is also good, being applied to the soil at the rate of 2 

 pints to 50 gallons of water. It can be applied with any sprink- 

 ling device. It is generally recommended that formalin be 

 applied at intervals of a few hours, until the whole amount has 

 been taken up by the soil, and frequent stirring of the soil is 

 necessary. Since formalin is extremely poisonous to plants it 



