Heterobasidion annosum (Fries) Brefeld Root fomes
Variable, sometimes possessing a cap, sometimes resupinate except for the upturned margin, flattened or shell-shaped, red-brown to blackish at the centre but pale at the margin, which when seen from below is always white. The tubes are in layers and like the pores, flesh and spore-print are white. The spores are broadly ellipsoid, small, smooth, hyaline and 4-5 × 4 µm. The flesh is fairly tough as it contains both generative hyphae and skeletal hyphae. It is frequent on the roots and lower parts of stems of many trees and shrubs causing a rapid heart-rot of conifers and extensive damage to young trees.
Illustrations: LH 67; NB 1111; WD 981.
The spores of all the perennial polypores described above do not blue when placed in solutions containing iodine.
Plate 48. Woody fungi: Spores borne within tubes—perennial polypores
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Schizophyllum commune Fries Split-gill fungus
Cap: 10-25 mm. Stem: width 2-4 mm; length 2-4 mm.
Description: