WILT, OR STEM ROT. 173 



Unquestionably another fruitful source of in- 

 fection comes about through the practice of pulling 

 off partly decayed leaves from the young plants 

 as they are growing. It is, of course, necessary to 

 keep the plants clean, but in all cases a knife 

 should be used for trimming both leaves and cut- 

 tings. If a leaf is pulled off it frequently leaves a 

 scar on the stem and this scar offers an excellent 

 opening for the fungus, which is likely to be present 

 in the soil or on decaying bits of organic matter 

 surrounding the plant. If the leaf is cut off, 

 leaving a short stem, the wound heals before the 

 fungus has an opportunity to gain entrance. 



The method of propagation has an important 

 bearing on the trouble and for this reason we have 

 been profuse in our statements regarding the im- 

 portance of using only vigorous stock. The prac- 

 tice of dividing the plants carries some of the dis- 

 ease over each year, and it will be seen that if this 

 is kept up it is only a question of time when the 

 stock will become so weakened as to be practically 

 worthless. The advantage of rooting cuttings in 

 sand that is absolutely clean is also apparent, for in 

 such cases the fungus, which might be in the 

 young roots taken from the soil, is eliminated. 

 Where the plants are simply divided and even 

 where they are removed as offshoots early in the 

 spring, the young roots often show the disease. 

 The difficulty, however, is most serious where the 

 fungus has attacked the stem, for in such cases the 



