6 Wood Discoloration

8.4 Damage to Stored Wood and Structural Timber Outdoors 201
S. commune and T. versicolor. On tree residues remaining in the forest (top,
branches) grow e.g., B. adusta, C. purpureum, Coniophora puteana, Gloeophyllum
sepiarium, Stereum sanguinolentum and T. versicolor. Forest-litter
degrading Basidiomycetes were described by Frankland et al. (1982).
Damages on roundwood (logs, poles) and boards may occur during transport
and inappropriate storage e.g., by C. puteana, Fomitopsis pinicola, Gloeophyllum
trabeum, Paxillus panuoides, Phlebiopsis gigantea, S. sanguinolentum
and Trichaptum abietinum. Wood chips are damaged by B. adusta, Gloeophyllum
spp., Phanerochaete chrysosporium, T. versicolor, and by several Deuteroand
Ascomycetes (molds, blue-stain and soft rot fungi). Several bacteria, yeasts,
Deuteromycetes and Ascomycetes were found in stored annual plant residues,
like sugarcane bagasse (Schmidt and Walter 1978).
Yeasts commonly colonize twigs, leaves, litter, and humus, are however also
found on freshly sawn lumber (Mikluscak et al. 2005).
Structural timber that is used outdoors in ground contact, like sleepers,
poles, posts, fences, bridges and garden furniture, is attacked by soft-rot fungi if
it is insufficiently treated with wood preservatives. Among the Basidiomycetes
occur e.g., Antrodia vaillantii, H. annosum, Lentinus lepideus, Leucogyrophana
pinastri, Oligoporus placenta, Phanerochaete sordaria, Phlebiopsis gigantea,
Serpula himantioides, Sistotrema brinkmanni, Trametes versicolor and Trichaptum
abietinum (e.g., Lombard and Chamuris 1990; Morrell et al. 1996).
Mine timber was decayed by A. vaillantii and C. puteana as well as by
Armillaria spp., G. sepiarium, H. annosum, L. lepideus, L. pinastri, O. placenta,
Paxillus panuoides, Schizophyllum commune, Serpula lacrymans, Stereum spp.
and T. versicolor (Eslyn and Lombard 1983). Earliella scrabosa, Loweporus
lividus, Rigidoporus lineatus, and R. vinctus were isolated from gold mine
poles in India (Narayanappa 2005).
Wood in fresh water, like in cooling towers, is often destroyed by soft-rot
fungi. Among the Basidiomycetes, e.g., Donkioporia expansa and Physisporinus
vitreus have been isolated from cooling-tower woods (v. Acker and Stevens
1996). The latter fungus degraded pine sapwood samples that showed a final
moisture content of up to 320% u (Schmidt et al. 1996). Schwarze and
Landmesser (2000) hypothesized that the preferential degradation of tracheidal
pit membranes is associated with the adaptation of this fungus to very wet
substrates. Wood in salt water below (not permanent) the sea level, as in harbor
constructions, is predominantly attacked by Deuteromycetes and Ascomycetes
and rarely by Basidiomycetes (Jones et al. 1976; Kohlmeyer 1977; Leightley
and Eaton 1980). Basidiomycetes, like Antrodia xantha, Daedalea quercina,
Gloeophyllum sepiarium, Laetiporus sulphureus, Lentinus lepideus, Phlebiopsis
gigantea, Schizophyllum commune and Xylobolus frustulatus dominate in wood
above the water level, like in docks, stakes or boats (Rayner and Boddy 1988).
Damages on stored and structural timber in outside use can be reduced or
even avoided by means of protection measures against fungal activity described
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