SAP-STAIlSr, MOLD, AND DECAY IN GEEElsr WOOD. 13 



Other fungi mentioned by Hedgcock (19) as blackening wood are: 

 Alternaria tenuis Nees., Stachyhotrys alternans Bon., Aspergillus 

 niger^ Chaetomium sp., Stemonitis sp., Gliocladiutn sp., Hormoden- 

 dron sp., H orniiscium sp., and Cladosporiwm sp. The apparent dis- 

 coloration in these cases is due either to the presence of colored 

 hyphse in or upon the surface of the wood or to a luxuriant super- 

 ficial growth of colored spore masses. In no case is it due to the 

 secretion of any pigment which is absorbed by the wood. 



Hedgcock {19) names three other species — PenicilliuTn aurew/i 

 Corcla, Fenicilliufn roseutii^ and a Fusarium sp. " formerly included 

 under Fusarium. roseum, — which, due to the secretion of soluble pig- 

 ments, actually stain the wood red, purple, or j^ellow, according to 

 the alkalinity or acidity of the medium. These stains are superficial, 

 however, and readily dress off when the lumber is planed. Many 

 other molds grow readily upon green sapwood and give the timber 

 a displeasing appearance, though they cause no deterioration in 

 the strength of the wood. From the material collected by the writer 

 and sent to the Madison laboratory there have been isolated over 40 

 distinct species of fungi. With the exception of species of Ceratosto- 

 mella and Graphium, together with a specie.s of Fusarium which was 

 identified by Dr. Mabel M. Brown, graduate student at the Uni- 

 versity of Wisconsin, as F. arthrosporioldes, this number consists of 

 fungi popularly known, as molds. The determination of the molds 

 was made by Dr. Charles Thom and Miss Margaret B. Church, of 

 the Bureau of Chemistry, United States Department of Agriculture. 

 They are listed below : 



Aspergillus flavus series. PemcilUum asperulum or puherulimi. 



Aspergillus niger. Penicillium brericaule series. 



Aspergillus repens. Penicillium commune. 



Aspergillus versicolor group. Penicillium divaricatum. 



Cephalothecium roseum. Penicillium lilacinum. 



Citromyces sp. Penicitlium luteum. 



Cladosporium sp. Penicillium purpurogenuni. 



Clonostachys sp. Penicillium roqueforti. 



Gliocladiutn sp. . Penicillium rugulosum. 



Haplograpliium sp. Penicillium solitum. 



Monilia sitophila. Syncepliala strum sp. 



Mucor sp. TricJioderma sp. 

 OidiAim sp. 



The great variety of genera and species here noted contains many 

 earth dwellers and indicates that the molds commonly found upon 

 green timber, especially during storage and transit, are for the most 

 part soil forms whose spores have by accident fallen upon the 

 moist surfaces of the sapwood and there found the conditions favor- 

 able for development. 



It has generally been supposed that the growth of mold on wood 

 is confined mainlj^ to the surface or, at the most, to the superficial 



