

 1 88 PLANT DISEASES 



living tree it should be cut out, and the wound dressed 

 with tar. As a rule the fungus attacks the lower part of 

 the trunk, gaining an entrance very frequently at those 

 irregularities of the surface which are kept constantly wet 

 by rain or dew trickling down the trunk. All dead trees and 

 fallen timber should be removed, as these serve as a nursery 

 for the present and numerous other species of fungi, which 

 live as saprophytes until an opportunity for attacking living 

 trees presents itself. 



FALSE TINDER FUNGUS 



(Fomes igniarius, Fries.) 



A wound-parasite, destructive more especially to oak- 

 trees, but attacking also apple, willow, alder, and various 

 other trees, exclusive of conifers. The fungus is perennial, 

 first appearing as a roundish knob, which eventually de- 

 velops into a hoof or bracket-shaped structure, four to 

 eight inches across, which usually remains thinner than in 

 the typical form of Fomes fomentarius. The upper surface 

 is minutely velvety when young, finally becoming bald, 

 reddish-brown, and at length blackish, very hard, and 

 more or less cracked and broken up into ridges. The 

 hymenium is cinnamon colour, the tubes minute, and in 

 old plants are stratose or arranged in layers. The flesh is 

 very hard, rusty brown, and zoned. Spores colourless and 

 almost globose. 



The present fungus superficially resembles Fomes fomen- 

 tarius, but is readily distinguished by the colourless globose 

 spores and very hard flesh, which is useless for making 

 tinder or fungus-felt. 



The wood of the host becomes brown during the first 



