Diseases and Injuries 



During some unfavorable seasons, it has destroyed almost the entire stock 

 of several growers. It is caused by a fungus, the spores of which exist 

 in the soil, and it apparently attacks a number of other plants besides the 

 carnation. It frequently attacks plants in the field, causing large loss, but is 

 usually the most destructive shortly after the plants are brought into the 

 houses in August and September. Thus far, comparatively little is known 

 about the disease, and probably less about preventing it. In my opinion, it 

 may be largely brought about by improper treatment of the cuttings in the 

 sand ; also improper potting of young stock ; that is, potting the plants too 

 deep ; also by planting the young plants too deep in the open ground. It may 

 be also increased by over-watering the plants, and by keeping them in a 

 close, warm, dank atmosphere. 



Applications of lime to the soil seem to have a tendency to reduce this 

 fungus, but thus far have not proved a positive preventive. The steriliza- 

 tion of the bench soil also tends largely to reduce the ravages of the fungus ; 

 but where the infected plants are taken from the open ground and planted 

 in sterilized soil, the disease continues its course, and the plants are destroyed. 

 In my opinion, if cuttings are taken from healthy stock, and rooted in 

 sterilized sand, then potted up in sterilized soil, and afterward shifted into 

 larger pots, say four to five inches, and held in a frame until June or July, 

 then planted upon benches filled with sterilized soil, these cuttings will re- 

 main practically free from the Stem Rot. 



I also believe that propagating young stock from exhausted plants has a 

 tendency to increase this trouble, as such stock is deficient in strength, and 

 succumbs much more readily to the attacks of fungi than stock propagated 

 from cuttings taken from plants which are growing vigorously. 



Some varieties are more inclined to Stem Rot than others, and the ex- 

 periments of the United States Department of Agriculture with disease- 

 resisting cotton plants would seem to indicate that rot-resisting varieties of 

 carnations could also be developed. 



There are two kinds of Stem Rot. The first is where the plant dies off 

 at the collar, and the entire plant is lost. This disease attacks the plant 

 very rapidly, and frequently carries it off in a single night. When a bench 

 becomes affected, the mycelium apparently travels through the soil from 

 plant to plant, causing great destruction. Sometimes as much as 90 per 

 cent, of an entire bench of plants has been destroyed by this disease. 



The second form of the Stem Rot might more properly be termed 

 "branch rot," as usually some branch, or only a portion of a plant dies. This 

 disease proceeds slowly, and may be usually noted by a single branch grad- 



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