170 PLANT LIFE 



the wood contains organic matter which is 

 either soluble or easily rendered so, and this 

 is one of the reasons why trees are felled at 

 a time of the year in which the wood naturally 

 contains least moisture or sap, and why the 

 tree is, or should be, left to " season " (i. e. to 

 dry) before being cut up. A source of danger 

 to stored timber may arise from contamina- 

 tion with organic matter consequent on the 

 neglect of proper sanitary precautions. For 

 wood which is so contaminated forms a very 

 suitable substratum for the germination of 

 a number of pests, and attacks of the 

 dangerous " dry rot " fungus (Merulius) has 

 sometimes been traced to this source. When 

 once a wood- destroy ing mycelium has estab- 

 lished itself in a piece of timber it may be 

 difficult to get rid of it. It will often lie 

 dormant for a considerable time when the 

 wood is dry, and only moisture or dampness 

 is required to awaken it to dangerously active 

 growth. 



The wood of living trees is liable to attack 

 by various fungi which commonly gain access 

 to it by means of wounds, due to abrasion of 

 bark or the falling off of branches. The 

 mischief is usually far advanced by the time 

 the first symptoms are apparent, and it is 

 often then too late to adopt remedial measures. 

 In these matters " a stitch in time saves 

 nine," and it is generally a simpler matter 

 to clean and tar a wound at once so as to 

 prevent the entrance of the disease-producing 



