X 



THE DISEASES OF PLANTS 



E W plants are exempt from 

 disease, and these exemp- 

 tions are seldom worth cul- 

 tivating, which is simply 

 another way of saying that 

 all desirable plants are sub- 

 ject to ills of one kind or 

 another. Some plants are of such strong and 

 sturdy constitution that they are able to with- 

 stand them without being greatly injured by 

 them, while others suffer under slight ones, and 

 often succumb altogether from severer ones, 

 unless prompt and energetic means are taken 

 to stay their progress. 



C Many plants are injured by overwatering. 

 Because of defective drainage surplus water 

 cannot escape from the soil, and as a result 

 it becomes sour, and the plants take on a 

 sickly look. The old leaves become yellow 

 and drop off. Their new ones are weak, 

 and the general condition of the plant is 

 highly unsatisfactory. If it is inclined to 



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