Deck 16: Wildfires

Question 1

Why are fires more frequent and hotter now than they were several decades ago?

Answer 1

Aggressive fire suppression for many decades.

Question 2

Why are fires more frequent and hotter now than they were several decades ago?

A) aggressive fire suppression for many decades
B) global warming
C) insufficient logging of trees
D) more insect-killed trees
E) weaker trees because of acid rain from power plants

Answer 2

A

Question 3

Between 2001 and 2009,what percentage of California forest fires was lightning-caused?

A) 2 percent
B) 5 percent
C) 7 percent
D) 13 percent
E) 30 percent

Answer 3

B

Question 4

Wildfires are beneficial to forests in all of the following ways EXCEPT:

A) thinning closely spaced trees.
B) reducing understory fuel.
C) permitting growth of different tree species and ages.
D) reducing insect infestations.
E) improving views.

Question 5

What condition does NOT lead to more fire-prone forests?

A) vegetation with large surface area per unit of volume of solids
B) low moisture content fuels
C) low-humidity air
D) larger trees
E) insect-killed trees

Question 6

Why do grass,needles,and shrubs burn easier and faster than trees?

A) They have a large surface area compared with volume of solids.
B) They are close to the ground where the fire is.
C) They are drier than trees.
D) They are closer together than trees.
E) They have fewer green leaves than trees.

Question 7

Which of the following techniques are NOT used to fight fires?

A) digging firebreaks by hand or bulldozer
B) igniting a burnout ahead of the main fire to remove fuel in front of the fire
C) planes or helicopters dumping loads of water
D) planes dumping loads of borate retardant just ahead of the fire
E) igniting a fire close to the wildfire to burn the area between it and the wildfire

Question 8

What are the main differences in a stream hydrograph after a large fire?

A) The hydrograph would be higher and narrower.
B) The hydrograph would be both higher and last longer.
C) The hydrograph would be lower but last longer.
D) The hydrograph would be unaffected.
E) The hydrograph would become skewed, rising more slowly but dropping very quickly.

Question 9

What is the principle cause of increased fire hazard to members of the public?

A) people placing their propane tanks near their houses
B) more people living in the woods building with wood
C) more closures of forest roads
D) more logging of large trees in forests
E) more people building in or next to forests or other wild lands

Question 10

Why do grass,needles,and shrubs burn easier and faster than trees?

Question 11

Which of the following aspects of wind does NOT accelerate fires?

A) It directs the flames to new fuel.
B) It brings in new air/oxygen to aid in burning.
C) It carries burning embers into new fuel.
D) It directs flames upward into the tree crowns.
E) It blows heat into areas of new fuel.

Question 12

How is fire danger or risk now determined over large areas?

A) Visible-light sensors on satellites measure the variable shades between green and brown.
B) Infrared sensors on satellites measure greenness versus average greenness.
C) Forest service personnel collect vegetation samples and analyze their water content.
D) Forest service personnel fly over regions to analyze for dry vegetation.
E) Fire lookout employees scan their region to analyze for dry vegetation.

Question 13

What are the main causes of forest fires?

A) lightning strikes, downed power lines and human carelessness
B) lightning strikes, downed power lines, and prescribed burns
C) downed power lines, arson, and prescribed burns
D) arson, prescribed burns, and human carelessness
E) downed power lines, prescribed burns, and human carelessness

Question 14

Why do lightning strikes in high mountains often NOT produce major fires?

A) Air temperatures in high mountains are almost always lower.
B) High mountains have less vegetation.
C) Since fire moves more easily uphill, there is not much fuel above them.
D) Vegetation in high mountains is often not dried out in summer.
E) Actually, they do, but those in such remote areas are often permitted to burn.

Question 15

Which side of a forest is at greater risk of wildfire in northwestern U.S.and southwestern Canada?

A) northeast
B) southeast
C) northwest
D) southwest
E) south

Question 16

What aspect of roads is most important for evacuation in case of a forest fire?

A) a straight road
B) a paved road
C) a road in a valley bottom so no fuel is downslope
D) vegetation cleared from within 50 feet of the road
E) more than one evacuation route

Question 17

What is LEAST necessary to start and maintain a fire?

A) fuel
B) high atmospheric pressure
C) warm temperatures
D) heat
E) oxygen

Question 18

Which of the following would NOT minimize fire danger to houses for people living in the woods?

A) clearing brush and trees around the house
B) using a metal roof
C) piling firewood next to the house
D) using fire-resistant material for a deck or covering it with fire-resistant material
E) maintaining and watering a lawn around the house

Question 19

Which side of a forest is at greater risk in specific parts of the continent? Why?

Question 20

Why is it dangerous to walk or drive in a small valley bottom in a big rainstorm after a major fire?

Question 21

What is the principle cause of increased fire hazard to members of the public?

Question 22

Describe the best things to do if you are trapped by a fire.Where should you take shelter to protect yourself and why?

Question 23

What are indefensible locations? Give an example of an area like this.If people choose to live in these areas,what do insurance companies require them to do to protect their homes from fire damage?

Question 24

What effect can topography have on the spreading of a fire? What are the dangers of being upslope during a fire?

Question 25

Lightning strikes high on hills or mountains more commonly than in valley bottoms.Why do such lightning strikes often not produce major fires? Be specific.

Question 26

Why isn't the Forest Service's Smokey Bear mascot now used as much as it was in the past?

Question 27

What are the three mechanisms by which fire ignites and progresses? Describe the mechanisms and how fire spreads.

Question 28

What is fuel loading? What are examples of fuel loading,and what makes them combustible?

Question 29

Why is a series of abnormally dry years more likely to create worse conditions for forest fires than a single year that is drier than any of a series of dry years?

Question 30

How can new fires start a kilometer from a forest fire,without lightning,arson,carelessness,or prescribed burns? Where would that be?