STUDIES UPON SOME CHROMOGENIC FUNGI WHICH 
DISCOLOR WOOD.* 
BY GEORGE GRANT HEDGCOCK, 
GENERAL REMARKS. 
The discoloration of unpainted woodwork exposed to 
moisture and to oxidation by the air is a familiar phenom- 
enon. Of course much of this discoloration is due to the 
dirt and soot which accumulate on the surface of boards 
in addition to the chemical changes which take place 
through weathering. There is also a class of stains of an 
entirely different nature and more striking to the eye. 
These occur on freshly sawn lumber in piles. It was in 
the investigation of the most important of these lumber 
stains in the study of the western yellow pine, Pinus 
ponderosa,t under Dr. Hermann von Schrenk of the Mis- 
sissippi Valley Laboratory, of the United States Depart- 
ment of Agriculture, that the studies upon which this 
paper is based were begun. In addition to the blue stain 
in pine lumber, brown, black, pink, purple and yellow 
stains and blotches were noted, not only on pine boards, 
but also on gum, poplar and other kinds. These were 
found to be caused by a number of fungi, some of which 
were quite different from that which causes the blue stain 
of the western yellow pine, viz: Ceratostomella pilifera 
(Fr.) Winter. Again the bluing of wood was found to be 
the result of the action of more than one species of 
Ceratostomella. | 
* A thesis presented to the Faculty of Washington University, in 
edndidacy for the degree of Doctor of Philosophy, April, 1906. Pub- 
lished by. permission of the Secretary of Agriculture. — Type cultures 
of all of the species described as new in this paper have been divided into 
parts deposited respectively in the United States National Herbarium, the 
Physiological and Pathological Herbarium of the United States Depart- 
ment of Agriculture, and the Missouri Botanical Garden Herbarium. 
+ Von Schrenk, H. Bull. Pl. Ind. 36: 1-27. (1903). (5 
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