Spalted Wood is beautiful looking when finished whether carved or turned
However it has it's own Hidden Health Dangers when using. Most people don't realize
what spalted
wood is when they are looking at it. Often, though, if you have multiple
pieces of wood laying out on a table, people are going to be attracted to the
piece that is due to it's unique and beautiful color and design in the wood.
What is Spalted Wood?
Spalted wood is wood that has just begun to be consumed by fungi and molds. As a result,
the mold and fungi dust can cause respiratory sensitivity, pneumonia or possibly idiopathic pulmonary
fibosis. EXTRA DUST PRECAUTIONS should be taken when turning or carving any wood that is spalted whether maple,
or any other wood.
Spalted wood is any wood that has begun to decay or rot as a result of a specific range of airborne fungus.
It is created when white rot fungus begins growing within a piece of wood or log.
When the fungus begins to grow within the wood, the process is referred to as is most likely to occur in hardwoods,
but can, if conditions are right, occur in softwoods as well.
In order for spalting to occur within wood, there are three conditions that must be present in order for the fungi
to grow properly. Those factors are temperature, oxygen and moisture.
Temperature
Studies have found that white rot fungi grows and spreads best when wood temperatures are between
70 and 100 degrees Fahrenheit.
Moisture
The moisture content of the wood needs to be above 25%. However,
wood can not be submerged in water due the fact that it prevents oxygen from
getting to the fungi. Keeping wood in a dark and damp location helps keep it
from getting too dry for the fungi to grow.
Oxygen
The fungi needs to be able to breath in order to grow. There is no set amount of oxygen needed in
order for the fungi to grow successfully.
Since spalted wood is a piece of wood that has begun to rot, it’s important that you stop the spread of the fungus before the
piece begins to lose its strength. In order to stop spalting from continuing, you simply place the piece of
wood in a dry location and prevent moisture from getting to it.
Myth
One of the most common myths that you may hear regarding spalted wood is that it is created from bugs, insects or bacteria
that is living in a piece of wood. These are simply not true. These organisms can (and do) live in
wood. They can also create designs in wood by boring holes into wood. However, designs or imperfections in wood caused by these
pests are NOT spalted wood.
Is spalted wood dangerous?
One of the biggest myths or misconceptions in the world of woodworking
is the perceived or assumed danger associated with spalted wood. It’s likely this myth began
because someone assumed that since spalted wood is associated with mold spores that it must be
extremely dangerous to work with.
With that said, you do need to take every bit of precaution when working with wood
(whether it’s spalted or not) to prevent the dust and spores from getting into your lungs.
There have been cases of people having allergic reactions to the inactive fungus spores contained within spalted wood.
You’ll find plenty of options available when it comes to masks to prevent you from breathing saw dust.
Studies have shown that spalted wood is actually no more dangerous to woodworkers or those who have
the wood in their homes than any other wood pieces.
Can spalted wood be used around food?
This is a controversial topic. Woodworkers will make the argument for
both sides. Thus far, there’s no true scientific findings on what the correct
answer.
The conservative viewpoint on this question is that it’s simply not worth the risk of using wood on pieces that are going
to be around food. Since spalted wood is made from fungus spores, people on this side of the argument conclude that there
is a risk of bringing food into contact with wood that has one point had fungus growing in it.
The folks on the other side of the argument claim that, we long as you aren’t using any types of wood with large pores (walnut,
red oak) that it’s perfectly fine to use spalted wood around food if you apply
food safe finish, such as this . The thought is that the
finish will seal any spores (dead or alive) into the wood and thus kill them.
Ultimately, this is a decision that will be left up to you as the woodworker. There are many beautiful things that can be made with
spalted wood, even if you decide to stay away from pieces to be used in the kitchen.
Tree Burls
Tree burls are another type of deformity that can appear on a tree that will significantly impact the grain, and color on a piece
of wood. Burls are different from wood in that their abnormality is often caused by damage that has occurred to a
tree. Burls are often described as a wart that has formed on a tree.
A burl will often appear on a tree due to some sort of stress that Mother Nature has inflicted, which can include an insect or
disease attack. As the burl grows, it will look; almost like a bubble growing from the damage section of the
tree. This distortion is what causes the wood grain and color to acquire it’s uniqueness.
Burls can come in a wide range of sizes. The difficultly to working with burls for woodworkers is the fact that burls are prone to
cracking or breaking due to the irregularities that have formed within them. Since their growth is due to stress or damage to the tree,
the inside of a burl could contain piece of bark that have been overgrown which could leave pockets or voids within.
The most highly desirable pieces of burl are those that have formed “eyes” within the wood grain. These are the most difficult
pieces to fine, and unfortunately you can not tell if a burl has created this look until the burl has been removed from the tree.
What is the difference between maple and ambrosia maple? These two types of maple can be similar but are
made in very different manners. As we’ve covered in the article above, spalted wood is created from fungus growing inside the
tree. Ambrosia is created by beetles that burrow their way into the trunk of a tree and discolor the wood as they tunnel through it.
