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All varieties of the plum and both tame and wild cherries are 

 attacked by this disease, the common bird-cherry and the native 

 choke-cherry being particularly subject to it. It is spread from 

 tree to tree by means of minute spores lig"ht enoug-h to be carried 

 by the wind. It is consequently of g-reat importance that in every 

 affected tree, whether tame or wild, the disease be promptly exter- 

 minated. Where it becomes <;-enerally distributed it is one of the 

 most destructive of all the diseases of the plum, and has obliterated 

 plum culture over extensive districts in the East. It does not af- 

 fect the tree generally and does not, indeed, extend far beyond the 

 ends of the knots. "Hence by cutting- of all affected parts it can 

 be kept from extending, except as it appears at newly infdctcd cen- 

 ters. When a tree is badly infected about the main branches it is 

 often best to remove and burn the entire tree to prevent the disease 

 spreading." Ordinarily it is sullicient to cut off diseased branches 

 a short distance below the last knot, and this may be done at any 

 time of the year. The cut surf.ice should be washed with Bor- 

 deaux mixture, and the diseaseil wooil should in every case be 

 burned, since it has been amply shown that spores may develop on 

 it to reinfect the trees. 



An'imikacnosk ()!• K*asimm':kkv. 



A fung'ous disease of the bark of the raspberry, blackberry, 

 and other closely related plants. "Appears on the canes at or near 

 the ground as very small purple spots which spread and soon 

 acquire a grayish-white center anil finally grow to a larg-e size, 

 then with a clearly defined purple rim; often uniting and covering 

 much of the bark; spreads to the petioles of the leaves when 

 abundant and eventually to the leaves themselves, occasionally 

 even to tlie fruit; spots often a quarter of an inch in diameter; not 

 penetrating the wood to any distance; surface opaque, slightly 

 ribbed longitudinally when old and assuming a scab-like character; 

 when at an advanced stage splitting and admitting water so as to 

 cause rot to extend into the underlying wood. Due to a well- 

 known fungus {^(t/ivosporiuiii I'ciiciiifn) which'causes the scab-spots 

 by attacking the bark, in which it remains dormant over winter. 

 Young shoots attacked by spores as soon as thev'appear in spring, 

 and most of the growth and development take place during the 

 growing season. Attack results in dwarfing growth and reduc- 

 ing quality and yield of berries. When very bad, berries may 

 shrivel up about time of picking, and not infrequently the canes 

 themselves die when the disease is of long standing. lUack 

 raspberries especially subject to it, in some cases to such an extent 

 that whole plantations are ruined. Anthracnose must not be 



