TWO NEW WOOD-DESTROYING FUNGI 
By James R. Weir, 
Forest Pathologist , Investigations in Forest Pathology , 
Bureau of Plant Industry 
* The opportunities afforded by the regular six months' field season, 
pursuant to the investigations in forest pathology in the great forest 
areas of the Northwest, have enabled the writer to collect the fungi of 
these regions with considerable completeness. In checking up the char¬ 
acters, affinities, and host relationships of a large number of species of 
wood-rotting fungi collected during the season of 1913 throughout Wash* 
ington, Idaho, Oregon, and British Columbia, some new and highly 
interesting fungi, not heretofore reported, have come to light. Brief 
descriptions of the distinguishing features of two of these species follow. 
Fomes putearius, n. sp.—Sporophores hard, woody, very irregularly lobed, recurv¬ 
ing, slightly conchate to applanate, occasionally broadly spreading to typically 
resupinate. The resupinate sporophores are often a foot or more in length. Pileate 
forms 12 to 14 by 6 to 8 by 0.4 cm. The surface in young specimens is velvety or 
tomentose, later becoming slightly encrusted, but always more or less corky, zonate, 
much wrinkled and furrowed in old age, in color deep brown, becoming darker; 
margin lighter colored, undulate, tomentose, thin, with narrow sterile border when 
young, later becoming thickened, rounded, and recurved by the successive annual 
layers; context corky to woody, thick deep brown; tubes irregularly but distinctly 
stratified 2 to 3 mm. long each season, but much longer in resupinate forms, brown; 
mouths uniformly oval, varying in size, 4 to 8 to a millimeters, edges thick, ferru¬ 
ginous; spores colored, globose, smooth, 7 to 8 pi; spines dark brown, slightly ventri- 
cose 13 to 25 by 6 jtt. 
This fungus (PL IX, fig. 1), in addition to certain well-defined char¬ 
acters of the sporophore, is chiefly distinguished from its nearest relatives 
by its most remarkable rot and its host relationships. The fungus is 
closely related to Fomes conchatus (Pers.), which is always found on the 
wood of deciduous trees, especially on oaks ( Quercus spp.) and willows 
(Salix spp.). Although many fungi show no discrimination between 
frondose and coniferous wood, F . conchatus , so far as the writer is 
aware, has not been reported on the wood of conifers, nor has it been 
collected in the West. Several collections at hand from southern Ger¬ 
many are all on the wood of broad-leaved trees. Fomes putearius , on 
the other hand, always occurs on coniferous wood, with a preference for 
larch (Larix spp.). The rot produced is one of the most conspicuous 
found in the northwestern forests and has determined the name of the 
fungus. The decomposition of the wood is quite similar to that produced 
by Trametes pini Fries, but the lignin reduction is on a much greater 
scale. The cellulose pockets produced by F. putearius are frequently 
more than 2 inches in length and vary in breadth according to the struc¬ 
ture of the host. A common type of the rot in larch is shown in Plate 
IX, figure 2. In yellow pine ( Pinus ponderosa) the pockets are smaller 
and more oval (PL IX, fig. 3); in Douglas fir (. Pseudotsuga taxifolia ) 
they are broadly oval (PL IX, fig. 4), while in Engelmann spruce ( Picea 
engelmanni) they are smaller than in any of the other hosts. This is 
(163) 
Journal of Agricultural Research, 
Dept, of Agriculture, Washington, D. C. 
Vol. II, No. 2 
May 25, 1914 
G—ai 
