Acacia – is a good choice for those who think about sustainability and eco-friendly living. This tree grows in many regions and it is dense and durable hardwood. It can withstand the elements. You can meet this tree in a boat building. Sealing acacia has beautiful golden brown color. If you decide to leave it unsealed, reserve this narrow outdoor bench for deck or patio because it can discolor after contact with the damp ground of a garden.