448 
Journal of Agricultural Research 
Vol. XXVI, No. io j 
appear after twenty to twenty-five days and a faintly purplish, slimy 
layer appeared on the agar slant. Following this, a network of jelly- 
like substance formed on the sides of the tubes above the agar surface. 
Examination disclosed this growth to be the plasmodial strands of a. 
Myxomycete which apparently had fed upon the hyphae in the cultures. 
At the end of thirty days no visible signs of hyphae were apparent. 
Three of the tubes continued to develop normal mycelial growth, and at 
the end of eight to ten days a brilliant carmine stain appeared on and. 
slightly below the surface of the agar. A subsequent study of the spore 
forms showed this organism to be a species of Fusarium. 
Following shortly on these observations the author had occasion to 
study several freshly felled boxelders on the campus of the University of 
Wisconsin. All of these trees showed an abundance of the red stain ex¬ 
tending from the roots to the smaller branches. It is most commonly 
found in the heartwood, but in many cases the discolored zone appeared 
in the inner sapwood, and isolated patches and irregular areas of color 
appeared in the sapwood nearer the bark (pi. 2). Cultures were secured 
from samples cut from the trees and transfers made to prune and oatmeal 
agars. Information from other parts of the United States where box- 
elder is cut in considerable quantity for commercial use indicates that 
this stain is very common and that it is a peculiar characteristic of this, 
tree. 
A preliminary note on the red stain of boxelder was published in 
March, 1922, by the writer in an article dealing with the economic aspects 
of certain stains commonly found in wood. 5 
The following taken from the article by Eidam( 4 ) is of historical in¬ 
terest in connection with the red stain in boxelder; he says: 
Greek mythology speaks familiarly of the dryads, those nymphs who live in trees- 
and are even said to suffer death with their felling. The ancient Greeks had been 
supported not a little in their poetic faith through the discovery of the blood red 
wood. We present-day skeptics take our microscope and prosaically attempt to probe 
the matter to the bottom. 
Hedgcock 5 has recorded the occurrence of a pink stain caused by 
Fusarium roseum (group) upon various species of pine lumber, but no* 
record is noted of its occurrence within the living hosts. 
HOSTS 
Boxelder, so commonly used as a shade tree, is the principal host of 
the organism producing red stain in the heartwood and to a less extent 
in the sapwood of the living tree. In this species of wood the stain has- 
often been traced throughout the heartwood in freshly felled trees from 
roots two inches or less in diameter through the trunk into the main 
limbs and out into the branches which measured from one to three 
inches in diameter. Similar but paler discolorations have been observed 
in the wood of yellow poplar (Liriodendron tulipifera Linn.), gumbo 
limbo (Bursera simaruba (Linn.) Sargt.), aspen (Populus tremuloides 
Michx.) and in white pine (Pinus sp.). 
Reports have been received of a red stain appearing near the juncture 
of sapwood and heartwood in white oak, but samples of this material 
‘Hubert, Ernest E. some wood stains and their causes. In Hardwood Rec., v. 52, no. 11, p.. 
17-19, 4 fig. 1922. 
•Hedgcock, George Grant, studies upon some chromogenic fungi which discolor wood. In - 
Mo. Bot. Gard. 17th Ann. Rpt., p. 59-114, pi. 3-12. 1906. 
