All ground contact poles (pine and gum) are SABS H4 treated against rot and insect predation. All cross braces and stringers (pine) are treated structural timber. We recommend that all timber be coated using a WaxOil preservative which we have used for over 20 years, with huge success. This preservative has proven to be cost-efficient and an effective treatment against the elements, especially in coastal areas. Fences installed 20 years ago are still standing and strong. An annual waxoil coating ensures optimal life of up to 20 years.