Fire and Climate History of Lowland Black Spruce Forests, Kenai NWR
  • Andrew De Volder
    US Fish and Wildlife Service, Sacramento Fish and Wildlife Office

Cataloging Information

  • black spruce
  • dendrochronological reconstruction
  • fire return interval
  • Kenai Peninsula
  • Picea mariana
  • stand age
  • tree ring
Record Maintained By:
Record Last Modified: November 12, 2015
FRAMES Record Number: 9900


In order to define the fire regime in Kenai NWR black spruce forests, a detailed fire and climate history study was undertaken. Utilizing techniques of dendrochronology I dated fire scars, and dated the outer-rings of fire-killed trees (burn poles) within areas of unknown fire history, and I analyzed the age-classes of living and dead trees. From a total of 1,022 cross-sections and 771 increment cores twelve fires were dated, the earliest of which occurred in 1708. Fire return intervals of the entire study are range from 25 to 185 years with an average of 89 years (S.D. = 43 years). The fire cycle of lowland black spruce forests was between 42 and 56 years. Analysis of the temporal pattern of fire events revealed a gap in fire occurrence between 1762 and 1828. Nine of the 12 fires occurred between 1828 and 1898, which was coincident with European settlement of the Kenai Peninsula. The gap in fire occurrence is proposed to have coincided with the onset of the coldest time period of Little Ice Age (the 19th century cold period). The also corresponds to a period of very low fire activity in western Canada, the western and southwestern United States, northern Quebec, and Sweden. This may be an indication of some larger Northern Hemispheric climatic shift at this time. The increase in number and frequency of fires after 1828 is attributed to, in part, an increase in human presence on the Kenai Peninsula and to more favorable climatic conditions.