Dec. 8. 2933 
The Red Stain in the Wood of Boxelder 
457 
The cause of the discoloration ranging from light coral red to hellebore 
red or carmine in the heartwood and to a less extent in the sapwood is 
due to the presence in the wood of a soluble red pigment produced by 
the colored hyphae of a fungus, Fusarium negundi Sherb. 
The fungus appears to be weakly parasitic since it is found developing in 
the sapwood following entrance through wounds principally caused by sap- 
suckers. The latter appear to be agents in the dissemination of the spores 
from different parts of a tree or from tree to tree. No evidence of pen¬ 
etration through living tissue in the absence of wounds has been noted. 
For uses where bright, stain-free stock is required the red-stained wood 
is rejected. Presence of the stain may degrade the stock and reduce 
the price per thousand board feet. The association of the red-stain 
organism with fungi-producing wood rot in the same tree necessitates 
caution in the use of affected material. 
The geographical distribution of the red-stain disease is assumed to 
coincide with the range of the boxelder. It has been found in many 
places in the United States, and what appears to be the same disease 
has been reported in a few places in Europe. 
As means of preventing the discoloration of the wood and as a pre¬ 
ventive measure in case the organism develops greater parasitic tenden¬ 
cies, sanitary measures directed to the proper care of wounds are 
suggested for shade trees; and for forest trees the burning of affected 
slash and the rapid handling of infected logs are believed to be of value. 
