General information on wood destroying basidiomycetes

Wood Decay Fungi Biology

basidia on gills

Section of a gill showing basidia and basidiospores on gill surfaces

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A higher magnification of a gill and basidiospores produced on basidia.

diagram of basidia on gills

Diagram of the basdia and basidiospores on a gill.

basidia in a pore

A section of a fruiting body with pores. The basidia (green), red is the mycelium between pores. The top left pore shows some basidiospores attached to basdidia.

basidia in pores

Diagram of basidia and basidiospores in pore.

basidia on teeth like structures

A section of a fruiting body with teeth-like projections. The basidia and basidiospores line the surfaces of the "teeth". Some younf immature basidiospores can be seen on the basidia. Red are detached mature basidiospores.

basidia on teeth like projections

Basidia and basidospores produced on the surfaces of the teeth-like structures.

clamp connections

Mycelium of a wood decay fungus. Hyphae can be seen with clamp connections which look like small bumps on the hyphae.

Clamp connections

Another wood decay fungus showing clamp connections on the hyphae seen in the middle of the photo.

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Higher magnification showing the clamp connections on hypha. The fungal hypha has been stained to see the clamp connections better.

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Brown rots

Brown rot in the field

A fallen tree on the forest floor degraded by a brown rot fungus. The advanced decay often breaks apart into brown cubicle pieces.

Brown rot in aspen

Brown rot in aspen

Brown rot close up

A closer look at the brown-rotted wood. When dry, it has little to no strength and breaks into fragments with slight pressure. When in the forest and wet, it can absorb moisture like a sponge. 

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White rots

early white rot in hardwood

In the early stages of white rot, before substantial strength properties are lost, the wood becomes lighter in color.

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White Rot in an aspen.

white rot in birch

A birch tree with decay fungi fruiting and advanced stage of white rot.

White rot in oak

A white rot fungus in oak. When you have a fruiting body on a tree (upper right) it is usually associated with a lot of decay inside the tree.

white pocket rot

Some white rot fungi are more selective at degrading lignin than others and cause a white pocket rot. The white "pockets" are pure cellulose and lignin has been completely removed.

zone lines in wood

Zones lines are produced when incompatable white rot fungi meet. The pseudosclerotial plate is a three dimentional barrier that keeps other fungi from invading their territory. These barriers can also form near wood surfaces to keep out fungi and protect against moisture loss.

zone lines in maple

The zone lines produced interesting patterns in wood. In early stages of white rot, this wood can be used for wood working since not much wood strentgh loss or biomass lost has taken place.

zone lines

Some additional examples of zone lines produced by white rot fungi.

Zone line art

Some extraordinary art can be made from wood with zone lines. Here is a piece with many different populations of decay fungi producing many different zone lines as each tries to maintain their niche. Note also the different stages of white rot and wood coloration from brownish (or normal wood color), to very white.

Zone lines

The zone lines are made up of compounds that resist attack and degradation by other fungi and also insects. Over time, as the wood all gets degraded, the zone lines persist.

Zones lines after decay

Another view of zones lines after all the wood has been degraded. After a very long time and all the wood is decomposed, Just the resisitant zone lines are left. This shows the 3 dimensional nature of the zone lines.