Which fuel type generally requires 100 hours to demarcate?

The fuel type that generally requires 100 hours to demarcate is medium fuels. Medium fuels typically consist of materials like small shrubs, grasses, or dead leaves that have a moderate drying rate and moisture content. This means they take about 100 hours to adjust and reach equilibrium with environmental changes, such as humidity and temperature.

This classification is crucial for fire behavior prediction since it helps firefighters understand how quickly a fire can spread in different types of vegetation. In contrast, fine fuels, such as dry grass or small twigs, will reach equilibrium much quicker—often within hours—due to their smaller surface area and lower moisture content. Heavy fuels, like large logs, will take significantly longer than 100 hours because of their thickness and moisture retention. Coarse fuels also fall into the same category as heavy fuels in terms of their long drying time. Understanding these classifications ensures effective fire management and strategy formulation.