Costs of landscape silviculture for fire and habitat management

In forest reserves of the U.S. Pacific Northwest, management objectives include protecting late-seral habitat structure by reducing the threat of large-scale disturbances like wildfire. We simulated how altering within- and among-stand structure with silvicultural treatments of differing intensity affected late-seral forest (LSF) structure and fire threat (FT) reduction over 30 years in a 6070-ha reserve. We then evaluated how different financial requirements influenced the treatment mix selected for each decade, the associated effects on FT reduction and LSF structure in the reserve, and treatment costs. Requirements for treatments to earn money (NPV+), break even (NPV0), or to not meet any financial goal at the scale of the entire reserve (landscape) affected the predicted reduction of FT and the total area of LSF structure in different ways. With or without a requirement to break even, treatments accomplished about the same landscape level of FT reduction and LSF structure. Although treatment effects were similar, their associated net revenues ranged from negative $1 million to positive $3000 over 30 years. In contrast, a requirement for landscape treatments to earn money ($0.5 to $1.5 million NPV) over the same period had a negative effect on FT reduction and carried a cost in terms of both FT reduction and LSF structure. Results suggest that the spatial scale at which silvicultural treatments were evaluated was influential because the lowest cost to the reserve objectives was accomplished by a mix of treatments that earned or lost money at the stand level but that collectively broke even at the landscape scale. Results also indicate that the timeframe over which treatments were evaluated was important because if breaking even was required within each decade instead of cumulatively over all three, the cost in terms of FT reduction and LSF structure was similar to requiring landscape treatments to earn $0.5 million NPV.