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Coral-Spot Disease. 



[JULY, 



One of the most common and most generally distributed of 

 British fungi is that to which the name of coral-spot disease has 

 been given. The first stage of the disease 



C °ral-Spot Disease. takes the f orm Q f bright coral-red warts, 



dead or dying branches of the tree attacked. These red warts 

 are very conspicuous, and at one time this condition of the 

 fungus was considered to be an independent plant, and called 

 Tubercularia vulgaris. At this stage numerous and exceedingly 

 minute spores are produced, and readily scattered by the wind 

 or by insects. 



At a later stage the coral-red changes to a rusty-brown colour. 

 The surface becomes rough with projecting points, and a second 

 form of fruit is produced. In many instances the fungus passes 

 through all its stages on dead branches, and when this is the 

 case no direct injury will be done but rather a certain amount 

 of good, consequent upon the hastened decay of the wood 

 upon which the fungus is growing. The indirect danger arising 

 from its presence on dead wood is the possibility of infection of 

 living plants by the spores produced. The earliest indication of 

 disease caused by JS'ectria cinnabarina is the drooping and 

 yellowing of the leaves, which soon die and fall to the ground. 

 A few weeks later the bark becomes slightly shrivelled, and the 

 characteristic coral-red warts begin to appear on the surface. 

 Death of the leaves, and finally of the branch, is due to the 

 choking of the wood vessels by the mycelium, which cuts off the 

 supply of water and food. 



The fungus is remarkable for the great number of different 

 kinds of woody plants upon which it can grow and produce 

 perfect fruit, being met with on all fruit and forest trees, 

 excepting conifers, and also on various shrubs. Amongst plants 

 specially susceptible to the attacks of Nectria may be mentioned 

 sycamore, elm, hazel, apple, pear, and red and black currants. 



Whenever diseased branches are observed they should be 

 removed and burned without delay, as after infection recovery 

 is impossible, and any delay in removal permits the formation 

 of spores and probable infection of neighbouring plants. 



Fallen branches, stored pea-rods, poles, &c, are often literally 



{Nectria Cinna- 

 bar i?ia?) 



which are about the size of millet seed, and 

 are thickly scattered over the surface of 



