244 The Farm Woodlot 



ment, the mycelia develop fruiting bodies on the outside of 

 the wood. These fruiting bodies are usually in the form 

 of a mushroom, toadstool or shelf fungus, but may have 

 many different forms. Some of these fruiting bodies are 

 renewed annually, such as the mushrooms, but the shelf 

 fungus renews itself by simply laying a new covering over 

 the old growth. In this new growth thousands of spores 

 develop and mature. From them the mature spores 

 start out to establish another generation of pests. With- 

 out such plants there would be no rot. 



Certain conditions are necessary to the growth of this 

 fungus. Without them it cannot exist. The most im- 

 portant of these are air and moisture. This may readily 

 be seen by examining a telegraph pole which has been in the 

 ground for some years. It will be found in very good 

 condition everywhere except where it enters the ground. 

 Here, especially if there is any sapwood on the pole, there 

 will be a ring of rot, because here alone we have the two 

 requisites, air and moisture present in sufficient quantities 

 to support fungus. In the upper portions of the pole, 

 there is plenty of air, but the supply of moisture is not 

 constant. Below the surface, where the soil holds the 

 moisture continually, there is not sufficient air. 



This accounts for the fact that timbers will lie, unim- 

 paired, for years on the arid desert where the wood dries 

 out very quickly after a rain. It explains why the piling 

 put in by the Lake Dwellers centuries ago is yet in good 

 condition, and why logs which have lain for centuries 

 under the water-soaked moss and debris in the woods of 

 Washington and Oregon show no signs of decay. The 

 air cannot get to them. 



