Post-fire conifer regeneration in severely burned southern Rocky Mountain ponderosa pine forests
Wildfire is an important disturbance in ponderosa pine forests of the southern Rocky Mountains. The last two decades have had fires of increased severity. The severely burned portions of these fires are generating concern about forest resilience, as there is uncertainty about ponderosa pine's ability to regenerate in areas where no surviving trees remain. Forest Service scientists collected post-fire conifer regeneration and other data in 600-plus, 100-square-meter plots to examine whether severely burned ponderosa pine forests of the southern Rocky Mountains are regenerating and how regeneration is related to environmental factors.
Their results from the Colorado Front Range indicate that ponderosa pine and other conifers have regenerated in severely burned areas, but at very low densities relative to unburned areas and to areas that burned less severely. Furthermore, their Colorado Front Range results also indicate that distance from surviving forest was the primary driver of conifer regeneration patterns, with very little regeneration observed in severely burned areas where surviving trees were more than 50 meters away.
They examined conifer regeneration in southern Rocky Mountain ponderosa pine forests burned by high-severity wildfire. They found that in the Colorado Front Range regeneration in high-severity burn areas was low relative to areas that burned less severely. They also found that in the Colorado Front Range, distance from surviving forest was the primary driver of regeneration patterns in high-severity burn areas, with regeneration declining as distance increased.
Ongoing analyses of the entire southern Rockies dataset will provide additional insight into patterns of conifer regeneration following high-severity wildfire across this broad region. These results suggest that Colorado Front Range ponderosa pine forests may not be resilient to high-severity wildfire, at least where surviving forest is not in close proximity. Ongoing analyses will provide additional insight into patterns of conifer regeneration following high severity wildfire across the broader southern Rocky Mountain region.