# what would cause these wood shavings?



## abfab04 (Jul 2, 2009)

I keep finding wood shavings on my deck steps. I can't see any ants or other insects but they seem to like the knots. Does anyone know what is causing this?


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## Nealtw (Jun 22, 2017)

This looks like something growing, fungus or mold. 
Is that treated lumber?


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## abfab04 (Jul 2, 2009)

yes pressure treated lumber. it feels rough like someone used sandpaper on it.


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## sdowney717 (8 mo ago)

Powder Post Beetles?
Any little holes?








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## joed (Mar 13, 2005)

All I am seeing is sap leaking from some knots in the wood. Normal and not insect damage.
The black does look like mold however.


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## abfab04 (Jul 2, 2009)

If it is sap wouldn't there be some liquid? Would dried sap cause the wood debris?
I don't see any holes but would have crawl under deck to check more closely.


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## joed (Mar 13, 2005)

I do not see wood shavings. I see particles of the sap that has fallen off.


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## Nealtw (Jun 22, 2017)

Sweep it up and get it tested.


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## RockyMtBeerMan (Dec 12, 2018)

Pine resin from the knots. Pinch some and smell it. 😎


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## Chris616 (Dec 31, 2019)

abfab04 said:


> If it is sap wouldn't there be some liquid? Would dried sap cause the wood debris?


Pine, fir and cedar trees produce resin in addition to sap. When that amber coloured, gooey substance is dried, like when lumber is kiln dried, the liquid resin crystalizes and produces a sold material just like what you’re seeing.


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## abfab04 (Jul 2, 2009)

Thank you all. I'm glad to know its not carpenter ants or a beetle causing it. Is there a sealer that I can put on it or should I leave it? We will be adding deck skirting on top of this. This is a joist and I don't want to have issues later.


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## Nealtw (Jun 22, 2017)

I think if anything would seal it, it would be shellac. 
Google says:
*Shellac based primers are great for sealing wood knots and sap streaks*. They do carry a pungent odour, but dry very quickly and will not let the knot bleed through the top (finish) coat.Feb 8, 2020


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