Simulation of Crown Fire Effects on Canopy Seed Bank in Lodgepole Pine

Abstract

Analysis of video footage taken of crown fires during the 1988 fire season in Yellowstone National Park indicated that the most frequent length of time required to completely burn tree crowns was 15-20 seconds. Lodge-pole pine (Pinus contorta Laws.) seeds were tested for ability to germinate after exposing both serotinous and nonserotinous cones for 10 to 60 seconds in a flame front designed to simulate a crown fire. Heating enhanced germination of seeds from serotinous cones but not those from nonserotinous cones. Maximum germination rates for serotinous cone seeds ranged from 37 to 64 percent and occurred after 10-20 seconds exposure of cones to flames. Germination after 60 seconds exposure averaged 0.3 to 14 percent. Maximum germination of seeds from nonserotinous cones (about 80%) occurred with no exposure and after 10 seconds in the flames.