How is the density of wood related to its ease of ignition?

The relationship between the density of wood and its ease of ignition can be understood through the concept of fuel characteristics and combustion. A denser wood generally contains more mass and moisture per volume, making it harder to sustain a fire compared to less dense wood.

When wood is dense, there is less air space within the material, which limits the amount of oxygen available for combustion. Additionally, denser woods often retain more moisture, which serves as a barrier to ignition because water needs to be evaporated before the wood can reach the necessary temperature for combustion. This means that higher density woods generally require more energy and time to ignite and start burning effectively.

In contrast, less dense woods tend to have more air pockets and lower moisture content, allowing them to ignite more easily and burn faster once ignited. Therefore, the statement that the denser the wood, the harder it is to ignite accurately reflects the behavior of wood during combustion, making it the correct answer. Understanding this relationship is essential for firefighters when selecting materials for fire control and understanding fire behavior.