Lidar Inventory and Monitoring of a Complex Forest

Strunk, Jacob; Reutebuch, Stephen; Foster, Jeffrey

The Fort Lewis Military Base in west central Washington State covers 35,025 hectares, 23,404 of which have significant tree cover (forests, woodlands, savannas). The undeveloped portion of the base is highly diverse ecologically relative to other western Washington forests. It is west of the Cascades Mountains yet its ecology is a blend of that found on both the east and west sides of the Cascades. Forest management balances the protection of the unique ecological niches found here with military training, fire management, timber production and human uses. A sparse grid of permanent forest inventory plots is used to monitor forest growth and conditions. Augmentation of the permanent forest inventory with aerial LIDAR measurements is currently under examination by the Fort Lewis Forestry Branch. The basic LIDAR-based inventory technique is to model inventory parameters with plot based LIDAR metrics. Application of models to the landscape results in a spatially explicit complete inventory of the forest. Preliminary inventory analysis in which only basal area was considered resulted in a linear model with an R2 of 0.86. The implication of this result is that the success found in modeling this variable at Fort Lewis may translate to similar success for other complex multi-use public forests where knowledge of landscape patterns is needed for planning and monitoring.