You think you are being attacked by some type of wood rot fungus and you need to apply some treatment to eliminate it. Wood is a natural and living material that can be affected by the action of both other living beings (biotic agents) and abiotic agents (temperature, water, sunlight, etc.). The possible consequences and effects are very varied and depend on multiple factors.
Before going into the subject, and starting to talk about possible wood fungi, it would be interesting to make a small diagram with the main types of biotic agents that attack wood.
- Mushrooms
- Chromogens
- Of rot
- Brown rot
- White rot.
- Soft rot.
- Insects
- Larval cycle insects.
- Woodworm.
- Weevil.
- Wood Wasps.
- Social insects
- Different types of termite.
As you can see, there are two large groups of agents that attack wood: fungi and insects. Here we will focus on the former.
Types of Xylophagous Fungi
Wood fungi often make an appearance in high humidity contexts. In nature, we will find them mainly in logs that have fallen and are in direct contact with the ground. While in human constructions they are more likely to be found in kitchens, bathrooms, basements or foundations.
Chromogenic fungi
As its name suggests, the action of this type of fungus has effects mainly on the color of the wood. Typically, the structure and physical and mechanical characteristics of the wood are not significantly affected by the action of this type of fungus.
Therefore, in most cases, they represent an aesthetic or visual quality problem for the wood and not a problem at the level of resistance. This does not mean that they are not a problem for certain sectors.
For example, logging companies may be forced to sell lumber at ridiculous prices for their viability, or consumers may see that some item in their home, in which they have invested good money, is no longer what they expected.
Wood Rot Fungi
These represent a more serious problem. They feed on structural components of wood, lignin and/or cellulose, causing significant deterioration in it.
There are different types, and we can include them in three groups according to the effects caused on the wood.
Brown rot
In this case, the fungus feeds on cellulose, not lignin. The wood takes on a brown color, hence its name, and cracks. The result can be a wood that appears burned, cracked; forming cubes or geometric figures.
Among these types of rot, brown is the one that most rapidly deteriorates the mechanical characteristics of the wood. Another risk associated with this type of rot is that it creates a particularly favorable environment for the attack of wood-eating insects.
White rot
The white-rot fungus feeds mainly on lignin and very little on cellulose. The result is a whitish, fibrous-looking wood; hence it is also known as fibrous root. It is the most common.
The result is highly variable, reaching in extreme cases weight loss of more than 95%.
It affects hardwood species to a greater extent. These have higher lignin content, unlike conifers.
Soft rot
The wood that is affected by this fungus acquires a particularly soft, almost gelatinous consistency. They develop inside the cell wall and feed mainly on secondary cellulose.
On certain occasions, and from a visual point of view, it can be confused with white rot.It occurs in contexts of, especially high humidity. It is common to find it in wood that is in direct contact with the earth.
Effects of Wood Rot Fungi
Wood rotting fungi produce much more serious effects than chromogenic fungi. Basically, they destroy the internal structure of the wood and weaken it. That is, they eat the wood and it loses useful section.
Treatment and Elimination of Wood Fungi
The first step to treat and eliminate fungi in wood is to know the reason for the appearance and proliferation of these. There are a number of environmental factors that lead to this appearance. They stand out:
Humidity. This is, without a doubt, the variable that will determine whether fungi will appear and proliferate in the wood. As we have pointed out, fungi only develop when humidity exceeds approximately 20%. If we can keep the wood below this humidity percentage, fungi shouldn’t be a problem.
How do you keep the wood relatively low in humidity? Indicating what needs to be done is easy, although in practice it is not always. We must facilitate ventilation and avoid water leaks. When it comes to timber structures, and we are in the construction phase, these types of issues need to be considered and planned to avoid the problem.
Temperature. There is a wide range of temperatures between which wood fungi can develop, approximately between 3 and 50 degrees Celsius. Within these, the especially favorable range is 30-35 degrees. Taking these values into account, the actions we can take in this regard are much more limited.