Macroscopically the white rot will appear as white spots on the
wood, indicating that it has eaten up all the lignin and left the
white cellulose behind. It does eat away the cellulose and
hemicellulose too, but the lignin is delicious to them. It will
appear fibrous, stringy, and spongy with the white pockets present.
Brown rot is the opposite and it eats the cellulose first and
doesn't do much to the lignin. it is brown in colour, and the
fibrous texture is lost quickly. There is a much greater diversity
of white rot, but brown rot can reduce the weight of a tree much
faster than white rot.
Microscopically, the fungi's hyphae secretes enzymes which
attack the S2 and S3 layers of the wood and move into the
tracheids. It will destroy all layers from the lumen out to the
middle lamella.
for Brown rot, there is extensive degradation of cellulose...the
S2 layers degrade fast, but the S3 layer is more resistant. The
fungi (examples to come) eat all the carbs (cellulose&
hemicellulose).
examples of brown rot include Gelophyllum sepiarium and
Oligoporus placenus.
examples of white rot include Trametes versicolor and Phellinus
pini
