INJURIES INDUCED BY PLANTS 



79 



Where the seed has 

 been drilled, the disease 

 spreads from the point 

 of attack in two direc- 

 tions ; where sown broad- 

 cast, it spreads centri- 

 fugally in all directions. 

 Should dry weather in- 

 tervene, or on the ap- 

 proach of autumn, the 

 disease ceases to spread, 

 but on examining the 

 roots of plants appa- 

 rently sound situated in 

 close proximity to those 

 already dead one will be 

 able to recognize nume- 

 rous examples of the 

 pathological symptoms 

 which have been already 

 indicated. If such dis- 

 eased plants are trans- 

 planted in the following 

 year, it will be a question 

 of weather whether they 

 die, and possibly trans- 

 mit the disease to neigh- 

 bouring trees, or form 

 a new tap-root, if the 

 apex was destroyed by 

 the disease, and, after 

 remaining stunted for 

 some years, slowly re- 

 cover. 



If a dead plant be 

 placed in a damp warm 

 chamber, or be planted 

 in July in the middle of 

 a bed of healthy young 



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