What part of the ladder is placed on the ground or other supported surface?

The butt or base section of a ladder is the part specifically designed to rest on the ground or another supported surface. This section provides the necessary stability and support for the entire ladder, allowing it to maintain balance and prevent tipping during use. Proper placement of the base section is crucial for safe operations, as a well-supported base helps ensure the ladder can effectively support the weight of firefighters or equipment being used or maneuvered at height.

The terminology reflects the ladder's construction: the butt or base section is closest to the ground, serving as the foundation for the remaining sections of the ladder, such as the extension section and the fly section. Each of these sections plays a role in extending the ladder upwards or providing access, but it is the butt section that provides the critical point of contact with the ground for stability and safety during operations.