Product Description
Wooden Pergola Single Beam 300 x 300 cm
Green treated” (aka pressure-treated) refers to wood that’s had preservatives forced into it, under pressure, to help protect it against decay and insect attacks.
Today, the most commonly used preservative is ACQ—Alkaline Copper Quaternary.
The copper in the solution is the chemical that imparts the green color; as the wood dries and reacts to sunlight, the color fades to gray.
Also please add that it is recommended that the wood is treated with garden furniture oil at least once a year in order to help preserve the color and keep the wood from drying out.