404 SYLVICULTURAL NOTES ON TIMBER TREES 



often doing very great harm to young trees and nursery 

 stock. 



Agaricus melleus ( = the Honey Fungus) characterised 

 by its black rhizomorph strands on the roots, and its mush- 

 room-like fructifications, attacks the roots. The needles of 

 infected trees turn pale, and the trees soon die. 



Trametes radiciperda ( = Pomes annosus), and known as 

 the Red Rot Root Fungus, often attacks trees of all ages, 

 which, when once attacked, usually quickly die. The needles 

 of trees, when attacked, turn pale ; and at the base of the 

 stem, or on the roots just below the soil, the bracket-like 

 fructifications may be found. These appear as somewhat 

 flat, corky incrustations or brackets with wrinkled margins ; 

 at first they are of a yellowish-white colour, but later on they 

 turn dark brown on the top, being snow-white underneath. 



Trametes pini attacks the boles of trees, usually after 

 they are about 35 years of age. Bracket-like fructifications 

 appear on the stem ; the heartwood rots away, and the tree 

 becomes hollow. The sapwood of Pines and also of Larch is 

 not affected, but the sapwood of Spruce and Silver Fir is 

 decomposed just like the heartwood. 



Peridermium pini acicola = The Pine Needle Blister, or 

 Bladder Rust, attacks the foliage of Scots and other Pines. 



Young trees up to 12 years of age are most frequently 

 attacked, though often older trees. New foliage is never 

 attacked, but only needles I or 2 years old. 



In the spring, small orange vesicles or blisters may be 

 seen on the leaves. 



Peridermium pini corticola = The Pine Bark Blister or 

 Canker, often does immense damage to Scots and other 

 Pines, especially on southern aspects. Young trees up to 

 about 1 5 years of age are chiefly attacked ; if it occur in older 

 trees, the attack is confined to the younger wood, the bark of 

 which is thin. 



It is characterised by the appearance on the smooth 

 young bark, of bladder-like pustules filled with yellowish-red 

 spores. 



Oaeoma pinitorquum, known as the Pine Shoot-twisting 



