Fake Christmas trees are typically made of materials such as plastic, metal, and sometimes even wood. The most common material used for fake Christmas trees is PVC (polyvinyl chloride), which is a type of plastic that is very lightweight and easy to mold into different shapes. Other common materials used for fake Christmas trees include aluminum, steel, and fiberglass. Additionally, some fake Christmas trees are made from real wood, but these are typically more expensive and less common than the plastic or metal varieties.