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Figure 2 -- Occurrence of 902 fires on USFWS lands in ND, SD, MN, MT, and NE, 1965-1984. GIF (4K)

Figure 3 -- Area burned on USFWS lands in the prairie pothole region, 1964-1984 (69,484 acres in total). GIF (4K)

Figure 4 -- Percent of 673 burns by size classes on USFWS lands, 1965-1984. GIF (4K)

Figure 5 -- Distribution of 69484 acres of burns on USFWS lands by state, 1965-1984. GIF (4K)

Figure 6-- Percent of burns by habitats on 60,999 acres of USFWS land, 1965-1984. GIF (4K)

Figure 7 -- Number of people used on 673 burns on USFWS land, 1965-1984. GIF (4K)

Figure 8 -- A regression of the relations of cost per acre on fire size. GIF (4K)

Figure 9 -- A regression of the relations of work-hours per acre on fire size. GIF (4K)

Figure 10 -- Setting a fire with a drip torch. JPEG (13K) -- GIF (55K)

Figure 11 -- Setting fire in grassland with a propane torch. JPEG (12K) -- GIF (37K)

Figure 12 -- Backing fires have short flame length and little smoke. JPEG (8K) -- GIF (37K)

Figure 13 -- Head fires produce longer lengh flames and lots of smoke. JPEG (5K) -- GIF (23K)

Figure 14 -- Flank fires burn at oblique angles to the wind direction. JPEG (15K) -- GIF (27K)

Figure 15 -- Backfire technique for burning graslands against the wind. JPEG (18K) -- GIF (71K)

Figure 16 -- Head fire technique for burning with the wind in grasslands. JPEG (6K) -- GIF (35K)

Figure 17 -- Spot fire technique for setting fire in grasslands. JPEG (11K) -- GIF (62K)

Figure 18 -- A pictorial description of how to set fire using the chevron burn technique. JPEG (19K) -- GIF (75K)

Figure 19 -- The ring, surround, or circular burning technique. JPEG (12K) -- GIF (74K)

Figure 20 -- Burning an island of grassland cover surrounded by cultivated land. JPEG (16K) -- GIF (62K)

Figure 21 -- Determining onsite fire behavior and wind and smoke direction from a small test fire. JPEG (15K) -- GIF (54K)

Figure 22 -- The basic burning plan for each burn should be outlined on a detailed aerial photograph or field map. JPEG (9K) -- GIF (40K)

Figure 23 -- The fire boss should keep the entire crew informed of his position during the sequence of the burn and of teh proceudre for constantg communication among all crew members. JPEG (13K) -- GIF (54K)

Figure 24 -- Two people starting a backing fire at the midpoint of the baseline when the wind is blowing perpendicular to a baseline firebreak. JPEG (12K) -- GIF (64K)

Figure 25 -- Back burning a buffer strip 30-60m (100-200ft) wide before setting a head fire. JPEG (10K) -- GIF (71K)

Figure 26 -- A barren soil firebreak made with a tractor and disk. JPEG (15K) -- GIF (80K)

Figure 27 -- Roads can be good fire breaks but smoke can be a problem sometimes. JPEG (11K) -- GIF (71K)

Figure 28 -- Using a wetland as a firebreak. JPEG (6K) -- GIF (34K)

Figure 29 -- Applying chemical retardant as a firebreak. JPEG (13K) -- GIF (85K)

Figure 30 -- Using a wetline as a firebreak. JPEG (20K) -- GIF (44K)

Figure 31 -- Containing a fire with a backpack pumper and a flapper. JPEG (14K) -- GIF (34K)

Figure 32 -- Burning unwanted buildings is best done when the ground has a full cover of snow. JPEG (13K) -- GIF (37K)

Figure 33 -- Percent of 657 fires by the primary type of firebreak in use on each fire on USFWS lands, 1965-1984. GIF (5K)

Figure 34 -- Average prevailing wind direction for some US Weather Bureau reporting stations. JPEG (23K) -- GIF (104K)

Figure 35 -- Percent of 775 fires by ambient air temperatures at the start of each fire on USFWS lands, 1965-1984. GIF (4K)

Figure 36 -- Percent of 636 fires by ambient relative humidity at the start of each fire on USFWS lands, 1965-1984. GIF (4K)

Figure 37 -- Percent of 808 prescribed burns by classes of wind speed at the start of each fire on USFWS lands, 1965-1984. GIF (4K)

Figure 38 -- Percent of 793 fires by 90-degree quadrants of wind direction on USFWS lands, 1965-1984. GIF (4K)