Which material is NOT commonly used for spray tanks?

The correct answer is wood, which is not a commonly used material for spray tanks. Spray tanks are designed to hold and handle various chemicals, including herbicides, pesticides, and fertilizers, and they require materials that can withstand corrosive substances and the physical demands of agriculture.

Stainless steel is often preferred due to its durability, resistance to corrosion, and easy cleaning properties. Aluminum alloys are also commonly used because they are lightweight and resistant to rust, making them suitable for mobile applications. Plastic reinforced with fiberglass offers additional benefits of being lightweight, resistant to chemicals, and easy to mold into complex shapes, making it an ideal choice for modern spray tank designs.

In contrast, wood does not provide the necessary chemical resistance and structural integrity required for a spray tank. It can absorb liquids, which could lead to contamination and structural failure over time, making it impractical in agricultural applications where clean and reliable performance is critical.