Slash pile burning is the most common method of logging residue disposal in Rocky Mountain forests. Federal regulations stipulate that management activities on Forest Service land must not permanently degrade the productive capacity of soils. Land managers therefore need information about the long-term consequences of pile burning to evaluate potential rehabilitation needs and alternative practices.
We previously identified a 50-year time series of slash pile burn scars created after clear cut harvesting in lodgepole pine stands, and found that tree colonization in scars was sparse across the entire time period. We visually observed evidence of high soil burn severity in the scars, including layers of soil charcoal and hardened red soil across the time series, leading us to hypothesize that soil changes may be playing a role in tree colonization patterns. Here we explored this hypothesis by examining soil nutrients and chemistry and conducting in situ and greenhouse seedling bioassays.