Which two preservatives are commonly used for treating wood poles?

• A. Tar and creosote
• B. Creosote and formaldehyde
• C. Tar and lime
• D. Water and salt

Answer: (A)

Wood poles need protection from moisture, decay, and insects to last outdoors. Creosote is a long-used preservative that soaks into the wood and provides strong, lasting protection against fungi and termites. Tar, when used as a coating, adds a waterproof barrier that helps resist weathering and moisture on the surface. Together, they form a traditional approach to pole treatment: creosote handles deep, lasting decay resistance, while tar adds surface protection. Other options aren’t as suitable for poles in ground or outdoor conditions, such as formaldehyde-based preservatives or simple water-and-salt mixtures, which don’t offer the same durable protection.