Conservation of Ancient Timbers from the Sea 279
of ‘start–stop’ apical growth of fine hyphae combined with cavity expansion
due to cell wall dissolution by enzymes released from the hyphal surface.
When viewed in transverse section, the cell walls of axial cells are perforated
with holes in the S 2 layer that represents cavities in cross-section (Figure 10).
Hyphae within the cavities continue to release enzymes and the cavities widen,
Figure 9Soft rot fungal attack of wood in cell wall. Note fungal hyphae in cavity (arrowed)
Figure 10Transverse section of oak showing soft rot cavity in secondary wall layer (arrowed)