I was wondering about spalting logs with specific fungi for more predicable results and I did find some information online. I am interested to know anyone’s experience with this kind of thing, what fungi they preferred and if anyone has tried inducing spalting on rough turned bowls. Could this speed up the process and give unique results or, due to the randomness of results, is it better to choose the spalted wood that is aesthetically pleasing first before putting in the effort of rough turning?
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Induced spalting on rough turned bowls?
- Thread starter Cai Robertson
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- green bowls spalting
The professor at the University of Oregon used to sell fungal samples for spalting. Looks like you now have to be a member of a coop: https://www.northernspalting.com/
My best grown spalting is when I use chain saw curls from other spalted wood to cover the wood. Just leaves and moisture take much longer to get it growing.
I haven’t tried it but I once heard from someone who tried without success. From my reading and experience, spalting best tales place in the log or solid blank.
The ultimate source to ask about spalting is Dr Sari Robbinson, sometimes known as Dr. Spalt. I have both of her books and the complexity of controlling spalting is deep. You might contact the good doctor and ask - I understand they are helpful. Sari used to offer different types of spalting fungi for sale for those who wanted to experiment.
I once knew a guy who operated a “spalting farm” where he stood log sections vertically in leafy dirt and waited. After some time he said he cut off a few inches and checked if spalting had started. From there, it was a matter of long experience to determine how far to let it go before it turned to rot. (The path between spalting and rot is short!)
My understanding of things needed for spalting: wood containing moisture, lots of yummy food (e.g. lignin & celulose , presence of hungry fungi, warmth, oxygen.
I’ve had good luck inducing spalting by putting solid blanks in a plastic bag with water. Note that the fungi need to be aleady on the wood for this to work. Fortunately, fungi are everywhere. If in doubt, take a freshly cut green blank outside and rub the end grain and sides around in the dirt.
Note that different species spalt differently. Some common spalted species we turners use are maple, birch, beech, hackberry, elm, oak and such, especially the lighter woods where the black zone lines are more visible and especially those with fine grain. I almost never saw spalted dogwood until I dug up an old dogwood stump in a neighbor’s yard - it has quite interesting color and zone lines.
(note that the black lines we associate with spalting are actually the zone lines the fungi create are walls of defense from competing colonies of fungi eating their way through the wood. The spalting is the wood, often colored by the growing fungi, between the zone lines.
JKJ
Sounds like a good way to get the fungi started.
I saw Dr Sari describe making spalting chambers at a symposium once. The idea was to take rubbermade totes, put in your green wood, put an inch or so of water in the bottom so it stays wet, inoculate with fungus and wait. After the first inoculation you can keep inoculating new batches with a couple pieces of the previous batch, and the tote will become "contaminated" with spores and will usually self-inoculate. The trick is knowing when the wood is ready, which is apparently had to predict and takes a combination of experience and meticulous record keeping of species, temperature, and time.
For most coloring (I don't know about the black lines) Dr. Sari actually recommends growing the fungus in agar, extracting the pigment, and painting it on the piece. This is faster and more controllable than letting nature take its course. Fungal dyes are also a thing in the textile world, so you might want to explore that rabbit hole for ideas.
For most coloring (I don't know about the black lines) Dr. Sari actually recommends growing the fungus in agar, extracting the pigment, and painting it on the piece. This is faster and more controllable than letting nature take its course. Fungal dyes are also a thing in the textile world, so you might want to explore that rabbit hole for ideas.
I have a damp area down in a corner of the back yard that has a small concrete slab around a metre square. This is my spalting lab 
I stack a few blanks here and cover the them with lawn clippings and throw a trap over them, 6-8 weeks late it pretty much done depending on the species, summer seems to be a better time.
I stack a few blanks here and cover the them with lawn clippings and throw a trap over them, 6-8 weeks late it pretty much done depending on the species, summer seems to be a better time.
The professor is Seri Robinson and she is actually at Oregon State University. If it is about spalting she is the person to ask. For more information check out https://www.northernspalting.com/about-us/dr-spalting/
Her email address - at least the one I have - is seri.robinson@oregonstate.edu
Seri is coming to our club next month as the featured demonstrator. I have heard she is really knowledgeable and entertaining.
Take good notes and let’s hear a summary!
So many great replies to point me in the right direction. Big thanks to everyone. I might try adding some spalted shavings from some different sources to a few rough turned bowls to see what happens. If it’s interesting I’ll be sure to post an update.
At AAW Seri presented several sessions and she also had a booth in the vendor area with a number of her students ready to speak to anyone about the wood technology coursework, spalting, etc.
I cut down two failing holly trees for a neighbor. I laid sections of log in the swale between our lots so the rain soaked them periodically. It spalted nicely!
Here’s my take on a Grecian Urn out of that wood.
I cut down two failing holly trees for a neighbor. I laid sections of log in the swale between our lots so the rain soaked them periodically. It spalted nicely!
Here’s my take on a Grecian Urn out of that wood.
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Excellent! I’ve never had nor have I seen spalted holly. Next time I get some I want to try that. (Although Iope my holly trees stay healthy - holly and golden rain tree are the best honeybee-attracting trees I know of.)
Seri is one of the more interesting demonstrators I have seen, mostly because every thing I thought I knew about spalting was wrong! If you are going to try to spalt rough turned bowls, you need a certain % of moisture content or it won't grow. I do not know what that % is though, but pretty wet, like slinging water on you as you rough it out.
robo hippy
robo hippy
I set holly into the swale between our home and the neighbor’s, and the rain and tall grass keep them fairly damp.