2l6 



The Canadian Horticulturist. 



HLACKHERRV RUST. 



SiR,_Euclosecl you will Hiul diseased Blackcap leaves (Souhegan). Please examine, 

 and let me know what the disease is. la it infectious, and what is the best thing to do 



for it? ^ „ „ „ 



Gko. Smith, Vamlla. 



The Blackcap leaves which you send are covered with blackberry rust, a 

 fuiT^us known to mycologists as Ca3onia nitens. Experiments have been made 

 to ascertain whether the mycelium, or portion of the fungus which grows in the 

 interior, is perennial ; it has been proved that it does live through the winter 

 on the underground stem, hence the Bordeaux mixture, or any of our excellen 



Flli 52. — C.K.dMA NlTKNS, OkAN(;K Kl >T ok TMK r.l.ACKP.KKKY. 



copper solutions, though effective in destroying the spores, will fail of entirely 

 destroying the fungus that produces them. 'I'he only effectual remedy is to root 

 out and burn up all affected bushes, as soon as seen, and before the yellow dust 

 his been blown to healthy plants. The blackberry, especially the Kittalimiy, 

 is badly subject to this rust. We have .almost L'iven up growing this excellent 

 variety on this account. 



