Wood Type

• Treated wood is made from yellow pine or spruce. This lumber is light weight, which is needed to account for the extra weight that the lumber will gain through the chemical treatment process. Additionally, yellow pine and spruce are long, open-grained woods, which allows for easier chemical penetration during the treatment process.
  
  

Pest Control

• Sodium borates are inserted into treated wood through pressure chambers. This chemical is used to protect the wood from termites, wood beetles and carpenter ants. Consequently, the treated lumber retains a chemical smell that resembles typical bug treatments found at local hardware stores.
  
  

Rot Control

• Alkaline copper quat is used for controlling decay through fungal infestation. This chemical turns the lumber green or, in some cases, copper brown. The insertion of this chemical, which is water born, swells the wood, causing it to be up to 1/8-inch bigger than normal. Once the wood dries out, it sometimes cups and warps. Additionally, over time, the treated lumber loses its resistance to rot and insects and may need to be replaced.
  
  

Soft Wood

• Treated lumber is considered softwood, making it easy to drive nails into the material. Nonetheless, softwoods are easily split on the ends during attachment. To combat this, the treated lumber industry adds a latex or epoxy to strengthen the wood.