I picked up some cheap wood that someone was getting rid of. He said it was used for a deck, and I can see it is painted red. How do I know if it is treated? (Also, anyone know what kind of wood it is?)

The wood in question is the small block sitting on top of oak veneer plywood.enter image description here

  • 1
    Similar query to this previous Question which as you can see was closed as off-topic. Wood IDs similarly are outside the scope of this SE, but that is a piece of fast-growth commercial softwood, referred to generically as SPF (spruce, pine, fir) because wood from the three species can be considered so interchangeable. – Graphus Dec 5 '17 at 7:44
  • Ah... That's really too bad about it being SPF... He pointed me at this when I said "do you have any hardwood" but I'm fairly inclined to be believe you since it seems just as soft (when tested via my fingernail) as the cheap 2x4's I have around. Should I delete the question, or leave it here for the mods to close? – DavidZemon Dec 5 '17 at 13:55
  • Interesting thing about hardwood/softwood distinction: It really is more about how they grow than their inherent hardness. There can be very soft hardwoods (basswood, for example) and very hard softwoods (yew, which is harder than hard maple on the Janka scale). – Katie Kilian Dec 5 '17 at 15:24
  • Not treated, btw. You'll see hatches on the face/edge where they are essentially trying to inject the mystery substance (cca/quant/whatever), and you'll see a difference in coloration between the edges and the core. – Aloysius Defenestrate Dec 6 '17 at 4:03
  • Not sure I agree necessarily with @AloysiusDefenestrate - I've never seen treated timber in my country with the hatch/needle marks (though I've seen in photos, so I do know some countries do this). Also color is a somewhat, but not totally reliable guide - different chemicals mandated in different countries/time periods have different color profiles. Color can indicate it was treated, but the lack of color doesn't prove it wasn't treated. If it is pine, I would say it's dark enough to look treated and I can't imagine untreated pine being used for decking (or looking that good afterwards!) – Dave Smylie Dec 11 '17 at 2:26

Since this is US/Canada, when you talk about "treated" I assume you're talking about CCA (Copper-Chrome-Arsenic).

The answer is simple enough - buy a test kit. Google on arsenic wood test kit. For instance, on Amazon you can find Industrial-Test-Systems-481396-W-Arsenic and Walmart sells Arsenic-481396-W-Quick-Wood-Field-Testing-Kit

  • CCA is not the only type of treatment, and i believe it's actually been phased out - so depending on the age of this wood, it may be treated but not at all CCA. This wood looks like southern yellow pine, which is frequently treated (non-CCA) and used for decking. I would assume that is the case here. – aaron Dec 20 '17 at 13:31
  • @DavidZemon - Pay attention to aaron's comment. I'm not sure if you really did mean CCA when you said treated. If you just assumed that "treated" means CCA, then you need to do some research. – WhatRoughBeast Dec 20 '17 at 16:29
  • Good to know. The fact that it's SPF ruins my original plans for this anyway (cutting board), but I'll remember that about CCA if I never need to test something in the future. – DavidZemon Dec 20 '17 at 21:16

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