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 Add this item to the list  Fomes rimosus Berk.
Page number:332 
Description type:Culture description 
Description:Fomes rimosus Berk.
Cultural characters: (PI. 111, Fig. 12; Pl. IV, Figs. 44 and 45).
Growth characters. Growth moderately rapid to slow, plates covered in four to six weeks. Advancing zone even, hyaline to white, submerged or sparsely downy. Mat with white border, changing abruptly to "clay color" (10.0YR5.8,/6.0), "yellow ocher" (10.0YR 6.8/9.0), or "buckthorn brown" (8.0YR4.8/6.5) (one week), later with greater range of colors, from white through "colonial buff" (6 0Y8.5/5.5), "cream-buff" (3.0Y8 3 4 5 "chamois' 2.0Y7.5 5.8 "tawny-olive" (8.0YR4.8/5.8), to "old gold" (3.0Y5.8/5.5) and "mustard yellow" (2.0Y7.8/7.5) (four to six weeks), the brighter colors frequently assumed by the older cultures being noteworthy, at first appressed, downy to cottony, becoming cottony-floccose, finally felty and tufted. Reverse unchanged below newest growth, then "ochraceous-tawny" (6.0YR4.9/6.3), "cinnamon-brown" (5.0YR3.0/3.0), and "Prout's brown" (5.5YR2.8/3.2). Odor none. On gallic and tannic acid agars diffusion zones weak to moderately strong, trace of growth on both media.
Hyphal characters. Advancing zone: hyphae hyaline, with simple septa, branched, 3.0-7.5 µm diameter. Aerial mycelium: (a) hyphae as in advancing zone, becoming yellow and brown; (b) fiber hyphae with walls slightly thickened, occasionally pale yellow, more frequently dark brown, branched, occasionally septate, 2.0-3.0 µm diameter. Submerged mycelium: (a) hyphae as in advancing zone, frequently branched; (b) crystals numerous, octahedral.
Type of rot: spongy yellow heart rot of living Robinia pseudoacacia.
Descriptions of cultural characters: Campbell (42), Davidson, Campbell, and Blaisdell (64), Humphrey and Siggers (92); Long and Harsch (98).
Fomes rimosus is usually considered to be specific to Robinia pseudoacacia, and this host relationship, along with the occurrence of unusually broad hyphae in the cultures, should aid in the separation of this species from the numerous other species that have identical key patterns.
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