In wildland incidents, which fuels are more likely to ignite and burn?

Fuels exposed to heat from the sun are more likely to ignite and burn because direct sunlight can significantly raise their temperature, reducing their moisture content and making them more susceptible to ignition. Sunlight can cause fine fuels, such as grasses and leaves, to reach critical temperatures where they can ignite, especially on warm, dry days. These fuels can catch fire more easily and sustain flames, which is a critical consideration in wildland fire behavior.

The characteristics of shaded fuels, heavily watered fuels, and fuels in moist conditions typically lead to a higher moisture content, making ignition less likely. Shaded fuels tend to retain moisture and do not dry out as quickly, while heavily watered fuels have excess moisture that acts as a barrier to ignition. Similarly, fuels in moist conditions have their combustion potential significantly reduced due to the presence of water, making them more resistant to burning. Hence, the dynamics of exposure to sunlight play a vital role in assessing fire risk in wildland incidents.