introduction fungi are plants that live off the cells of wood. **fungi need certain condition to...

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Page 1: Introduction Fungi are plants that live off the cells of wood. **Fungi need certain condition to live on the wood Dampness- moisture content above 20%
Page 2: Introduction Fungi are plants that live off the cells of wood. **Fungi need certain condition to live on the wood Dampness- moisture content above 20%

Introduction

Fungi are plants that live off the cells of wood.

**Fungi need certain condition to live on the wood

• Dampness- moisture content above 20%• Warmth• Stagnant still air• Food source (timber)• Spores

Page 3: Introduction Fungi are plants that live off the cells of wood. **Fungi need certain condition to live on the wood Dampness- moisture content above 20%

Two types of wood destroying fungi;1. Dry rot2. Wet rot

Non-wood destroying fungi 1. Sap stain

Page 4: Introduction Fungi are plants that live off the cells of wood. **Fungi need certain condition to live on the wood Dampness- moisture content above 20%

DRY ROTMC above 22%

WET ROTMC above 30%

Page 5: Introduction Fungi are plants that live off the cells of wood. **Fungi need certain condition to live on the wood Dampness- moisture content above 20%

Dry Rot

Most damaging form of fungal attack

Called dry rot because it leave the timber dry, powdery and in a brittle state.

Page 6: Introduction Fungi are plants that live off the cells of wood. **Fungi need certain condition to live on the wood Dampness- moisture content above 20%

How Dry Rot Develops

Stage 1The spores or seeds are blown around by wind or carried by animals, insects or even humans.Stage 2Spores land on damp wood, germinate and send out hair-like roots called “hyphae”

Page 7: Introduction Fungi are plants that live off the cells of wood. **Fungi need certain condition to live on the wood Dampness- moisture content above 20%

How Dry Rot Develops

Stages 3When established the fruiting body is wrinkled and pancake-shaped, with a white border and orange-brown centre.Stages 4When fully ripe the fruiting body will discharge millions of red dust spores into the surrounding air.

http://www.youtube.com/watch?v=47rQYoETWm4

Page 8: Introduction Fungi are plants that live off the cells of wood. **Fungi need certain condition to live on the wood Dampness- moisture content above 20%

***Prevention and treatment of Dry RotPrevention

Keep moisture content below 20%Keep area well ventilatedApply preservative- more in next topic

Treatment

Cut away all affected timber.(650mm from infection)Flame surrounding concreteApply (KW) fungicides(usually done by specialists

Page 9: Introduction Fungi are plants that live off the cells of wood. **Fungi need certain condition to live on the wood Dampness- moisture content above 20%

Wet rot

Only occurs in timber that is actually wet (MC 30% or more)

How it develops

Same as dry rot except it does not produce fruiting bodies.

Lands on timber and uses any dampness present to germinate.

Destroys the timber completely

Page 10: Introduction Fungi are plants that live off the cells of wood. **Fungi need certain condition to live on the wood Dampness- moisture content above 20%

***Prevention and treatment of Wet RotPreventionPreserve timber in contact with the ground using

prolonged immersion preservatives. (*more on preservatives later).

Treatment

Cut back affected timberApply three coats of fungicidal wood preservativeFinish wood with a water-repellent finish.

Page 11: Introduction Fungi are plants that live off the cells of wood. **Fungi need certain condition to live on the wood Dampness- moisture content above 20%

Sapstain Blue stain or sapstain

are terms used to describe wood that shows blue to greyish-black stains on its surface, caused by wood-staining fungi

Although it doesn’t effect the strength of the wood but it effects the application of some finished and overall appearance.