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Can you compost sawdust from wood products like MDF and plywood?

 
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I'm always looking for good carbon sources for my composting, and there's a woodshop near me that has limitless sawdust, but they cut MDF, particleboard, and plywood, which contain toxic glues.

Normally I would avoid this, but some sources say that the composting process breaks down the glues, and the formaldehyde even breaks down into useful nitrogen.

What do the experts here think?
 
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I'm not an expert, but I personally think using those materials in composting would make me uncomfortable.
 
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Yeah, that's the domain of remediation, not composting.

For me, it would be because I have a shit tonne of it and it otherwise goes to the dump, to be liberally sprinkled on everything for miles downwind of the corridor from where it is to where the truck takes it, and because I would happen to have the space to deal with it.

I think the first stage would be slow bacterial and fungal decomposition, involving a tarped pile of sawdust, in a depression or possibly a dug pit, kept constantly damp while I regularly apply aerated compost extract and fungal slurries featuring oyster mushrooms. My hope is that the fungi would break down and/or sequester the stuff we don't want in the soil, leaving mushroom compost. I think I would cycle it through a hot compost whose ultimate destination after it leaves my hands would be wood lot for fuel or fibre, and definitely not for food crops.

I would seek the opinion of our own Dr. Redhawk, should he pop by this thread, but I think the adhesives are largely the same sort regardless of the size of the wood fibres or pieces, regardless of the type of manufactured wood product, and those are what concern us in terms of entering our food systems.

-CK
 
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Good thinking Chris, This is indeed a remediation of toxic gick. You also have all the steps listed. Thumbs up Kola.

The way I would approach such a project is to first hot compost all the material with lots of greens (For this application grass clippings would be superior for getting the heat up) piled in the center of the heap and thick layers added to the rest of the heap.
(this heating is to soften the adhesives and get them to start breaking down)
Once that heating was done I would leave the heap as is and start adding mushroom slurries from woods acquired mushrooms (if they are growing on dead wood, they are the right types) this will get the wood products and by products (MDF is paper, particle board is glue and wood chips).
Once you have some good mycelium growing in the heap it is time to add the oyster spawn and spray the heap with a compost tea.
For such a project you will need to think about a full 12 months of remediation and after that you can build a new compost heap, using some of the remediated materials in some of the new heaps layers.

The adhesives used for both MDF and Particle/flake board are fairly persistent unless you take the time to fully remediate the base materials, a second "composting" insures that you have given those materials the time and organisms to see a full conversion to harmless compounds.

Redhawk
 
Joshua Frank
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Thanks for the detailed answers. Though it pains me to resist a free and plentiful resource, dealing with the load of poison isn't worth it.
 
Bryant RedHawk
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hau Joshua, I think your decision should be more based on the amount of time you are willing to spend preparing those resources rather than rejection of the materials based on the idea they are poisons.

I do understand though since it would take a lot of time to get those contaminates broken down into useable, safe substances.

Glues like those used in MDF and Particle/ Flake board are more contaminant than poison actually.
It would be closer to an oil or paint spill than an outright chemical designed to kill plants or pests.

Redhawk
 
Joshua Frank
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I take your point, Redhawk. I was asking because I'm looking for a source of sawdust for composting, without a lot of pre-processing.  If my problem was that I HAD a lot of MDF sawdust already, I would definitely try your techniques to remediate it.
 
Bryant RedHawk
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Cabinet shops are rather notorious for using plywood and other than solid wood products since they are looking for long term stability of the materials.

If you have a mill works (place that makes moldings for high end houses and buildings) you might find exactly what you are needing.
home builders also might be a good hunting ground for pieces of non treated lumber pieces you could turn into chips.
I have a fairly small chipper and I use it for the pieces of wood to small to use for other projects or purposes as I cut my wood lot.

Some times you can even find a source from logging companies (you might have to rent the chipper but they usually "stump" the trees before they go to the mills)
If they don't have one of the giant, super expensive butt end grinders, they would have a huge pile of those cut off stump ends piled up at their work site.
(in N. Carolina there is a family that turns giant pieces of wood, they found a logging company and now buy their butts for just a small amount of money per piece)
 
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http://woodheat.net
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