182 FOEESTEY WOBK 



male is somewhat smaller. The body is banded black 

 and yellow, and the wings are like yellow gauze. The 

 larvae live in logs of timber for two or three years, and 

 the mature insects often emerge after the timber has 

 been used for building, etc. 



Spruce, Silver Fir, and Larch, are also attacked. 



Sirex Juvencus. — This insect resembles the previous 

 one in nearly all but colour, which is a steely blue. 



Fungi, 



Trametes Pini (the Stem-Rot Fungus). — This disease 

 attacks Pines from forty years or so and upwards, and 

 causes white rot in the heart of the trees. The mycelium 

 usually grows between the annual rings, separating them. 

 The brown sporophores are very similar to an oyster- 

 shell on top, softer underneath. All diseased stems 

 should be cut out before becoming rotten. 



Trametes Badiciperda {the Boot Fungus). — Attacks the 

 roots of Scots and Weymouth Pines, and also Spruce and 

 Silver Fir, causing red rot, which spreads upwards, 

 causing the tree to die and rot. The sporophores are 

 usually found on roots just below the surface of the ground, 

 between the scales of bark. The mycelium spreads in a 

 white felty layer between the bark and the wood. In- 

 fection can take place by the contact of diseased roots 

 with healthy ones, or the spores can be carried from one 

 tree to another by mice. It is about the most de- 

 structive disease in our woods. The needles turn lasty- 

 brown on infected trees. Hardwoods should be planted 

 on areas affected. 



