What is NOT a type of surface fuel in wildfires?

In the context of wildfire behavior and fuel types, surface fuels are those that are located on the ground and can catch fire easily. Trees, grass, and leaves are all considered surface fuels because they can readily ignite and contribute to the spread of wildfires. Trees, when dead or suffering from disease, can have combustible materials like bark and understory vegetation, while grass represents fine fuels that burn quickly. Leaves, particularly when dry, can also aid in the fire's expansion.

Bedrock, on the other hand, is solid rock and does not burn. It does not provide any combustible material that could be ignited in a wildfire. This makes it distinctly different from the other options listed, which all have the potential to catch fire and contribute to wildfire spread. Understanding the various types of fuels is crucial for fire behavior predictions and effective wildfire management strategies.