How to tell if wood is pressure treated?

To determine if wood is pressure treated, you can look for several indicators

Color: Pressure-treated wood often has a distinct greenish tint, though it can also appear brown, depending on the chemicals used. This tint is more uniform than natural wood grains.

[1] https://static.wixstatic.com/media/28462a_82fdc880e62549e2be94d68b317fd9d8~mv2.jpg/v1/fit/w_747%2Ch_384%2Cal_c%2Cq_80,enc_auto/file.jpg

Stamp Marks: Look for stamp marks or tags on the wood. Pressure-treated wood is usually marked with stamps indicating that it has been treated, along with the type of chemical used and the intended use (e.g., above ground, ground contact).

[2] Understanding Grade Stamps. https://www.treatedwood.com/news/understanding-grade-stamps-on-lumber

Weight: Pressure-treated wood is typically heavier than untreated wood because of the chemicals that have been infused into it.

[3] Pressure Treated Lumber Weights. https://www.engineeringtoolbox.com/green-kiln-dried-pressure-treated-lumber-weights-d_1860.html

Smell: Some types of pressure-treated wood have a noticeable chemical odor, especially when new.

Texture and Appearance: The surface of pressure-treated wood might appear slightly oily or have a slight residue, which is another indicator of the chemicals.