266 



Minnesota Plant Diseases. 



jn rt 



'' 



A parasitic life has not been demonstrated for it, but its pres- 

 ence in the wood of living trees is known. It is frequently 



found on shade trees, 

 especially on trunks, 

 which have been pruned 

 and not subsequently 

 protected. The fruiting 

 body is pure white and 

 usually large, often at- 

 taining a length of six 

 or seven inches and an 

 equal cap width. It is 

 usually fleshy and the 

 stem is slightly removed 

 from the center of the 

 cap (eccentric). The 

 spores are pure white. 

 The fruiting bodies are 

 frequently clustered. 

 This is a popular edi- 

 ble fungus. 



Several other close- 

 ly related forms are 

 likewise saprophytes on 

 timbers. Of these the 

 oyster fungus (Pleuro- 

 tus ostreatus) and the 

 sapid fungus (Pleuro- 

 tus sapidus) are best 

 known and very com- 

 mon forms. They are 

 all three prized as edi- 

 ble mushrooms. (See 

 also frontispiece and 

 Fig. 20.) 



The pine Lenzites 

 [L en zit e s abietina 



(Bull.) Fr.]. This is an exceedingly common timber rot on soft 

 Avoocls. It occurs on railroad ties, fence rails and posts and on 





