i9o6.] 



Tree Root Rot. 



113 



the bark and give origin to the white mycelium, which eventu- 

 ally kills the tree. These underground rhizomorphs travel for 

 an unlimited distance in the ground, and, unless checked, con- 



I. — Cluster of Armillaria Mellea. II. — Rhizomcrpii; on Root. 



stitute a continual source of danger to trees surrounding the one 

 attacked. 



When a tree is attacked a portion of the bark at the collar 

 should be removed, and if the white mycelium is found to have 



K 



