CPFM Fuels Management & Vegetation Flashcards

What is the primary objective of using prescribed fire for fuels management?

Answer: Reduce hazardous fuel accumulations that could contribute to severe wildfires

Prescribed fire reduces accumulated fuel loads that historically would have burned in natural low-intensity fires, preventing dangerous fuel buildups that cause catastrophic wildfires.

Which fuel type has the greatest influence on the rate of spread during a prescribed fire?

Answer: 1-hour fuels (grasses, leaves, pine needles)

1-hour fuels such as grasses and pine needles dry rapidly and carry fire most quickly, making them the primary driver of rate of spread in prescribed burns.

What is 'fuel loading' as used in prescribed fire management?

Answer: The dry weight of combustible organic material per unit area

Fuel loading is the dry weight of all combustible organic material per unit area (typically tons per acre), used to predict fire intensity and plan treatments.

What is the 'duff layer' in a forest floor and why is it a concern during prescribed burns?

Answer: The partially decomposed organic layer between litter and mineral soil that can smolder for days

The duff layer is partially decomposed organic material that can hold fire for extended periods after a burn, increasing the risk of post-burn escapes and making complete extinguishment difficult.

What does the term 'carry' mean in fire behavior when applied to prescribed fire planning?

Answer: The ability of fuels to sustain and transmit fire continuously across an area

Carry refers to fuel continuity and condition — whether fuels are connected and dry enough to sustain fire spread across the intended burn unit without gaps extinguishing the fire.

Which surface-area-to-volume ratio characteristic makes grasses ignite and burn faster than large woody debris?

Answer: Grasses have a higher surface-area-to-volume ratio, allowing rapid moisture loss and heat absorption

The high surface-area-to-volume ratio of fine fuels like grasses allows rapid moisture exchange with the atmosphere, making them dry quickly and ignite more readily than larger fuels.