Fire

1950

1995

1957

1976

1974

1966

Historical wildland fire perimeters.

Contains fires greater than 400 ha

between 1950 and 1992, inclusive

and fires greater than 40 ha between

1993 and 1997. 1998 data unconfirmed.

1976

Reported start locations placed for fires

greater than 400 ha for which no

perimeter map has been located.

Data from: BLM Alaska Fire Service,

Fairbanks, Alaska, 1998.

Figure 32. Distribution and extent of forest fires within Ft. Wainwright, central Alaska, 1998.

30 yr). Midsuccessional ecotypes (Upland and

Fire

Lowland Broadleaf and Mixed Forest types) occupy

Fire is a frequent and widespread disturbance

~19% of the area. Late successional types (Upland

in interior Alaska that causes well-documented

and Lowland Needleleaf Forests) occupy ~27% of

stages of vegetation succession (Lutz 1956, Viereck

the area. The late successional types Lowland Tus-

1973, Van Cleve et al. 1983). In our study area, com-

sock Bog and Lowland Wet Scrub (not including

pilation of forest fire distribution through histori-

low scrub-post burn vegetation type), which have

cal reports and remote sensing by the Alaska Fire

little tree cover and poorly understood succes-

Service reveals that approximately 30% (110,108

sional development and fire history, occupied 8%

ha) of the study area has been burned since 1950,

of the area. Additionally, some of the thermokarst

although a substantial portion of this burned area

complexes include some burned areas.

(17,294 ha) has burned more than once (Fig. 32).

Effects of fire on ecosystem development depends

Despite the general nature of the wild fire data

on the nature of the ecosystem (i.e., species, life-

(some fires are not documented and some fire

history characteristics, soils), and the severity and

perimeters may enclose unburned areas) and the

frequency of the fire (Viereck 1973, Van Cleve et

difficulty in determining the successional status of

al. 1983). Severity of the fire will affect how much

some shrub communities, the fire data and veg-

of the organic matter on the forest floor is burned

etation data compare well. The abundance of early

and subsequent regeneration pathways. In gen-

successional ecotypes related to fire (Upland Moist

eral, forest stands are replaced by the same tree

Tall Scrub, Upland Moist Low Scrub, Closed and

species (Viereck 1973, Van Cleve et al. 1983). On

Open Low Scrub vegetation types within Lowland

moist upland sites (white spruce sites), Foote

Wet Low Scrub, and Lowland Gravelly Wet Low

(1983) identified six distinct successional stages: (1)

Scrub, see Table 9) indicates that ~5% of the entire

newly burned stage during 03 years, (2) herb-tree

study area has been burned recently (within about

60

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