FORSight Resources Library


The staff at FORSight Resources work hard to stay current with the latest technologies and research in their respective fields by attending conferences and symposia, where they often present findings from research they have completed. A selection of papers, presentations and white papers authored by FORSight staff is available for download below. Note, you must have Acrobat Reader to view these files.


Management of Timber Under a Habitat Conservation Plan (HCP) in the Pacific Northwest (2007)
Karl R. Walters and Gene McCaul
West Fork Timber Company (WFTC) is a private timber company that manages approximately 55,000 acres on the western slopes of the Cascade Mountains. West Fork's goal was to develop a long-term harvest plan that would improve asset value over time, while simultaneously ensuring that habitat requirements set forth in their Habitat Conservation Plan (HCP) would be realized. The primary constraint set forth in the HCP is the maintenance of a unique Dispersal Landscape Index (DLI) within a narrow (+/- 5%) range of pre-determined levels for the life of the HCP. The DLI is derived by assigning different values to areas within specific distances of existing dispersal habitat (DH) in a complex formula; the dispersal habitat (DH) values are then summed and divided by the total number of acres in the forest to arrive at a DLI value for the ownership. This paper discusses DLI calculation and the challenges involved in modeling this problem, including the types of constraints needed in the strategic model, the spatial allocation of activities associated with existing and future stands in a Model II framework, and the development of a rapid DLI calculator to facilitate the evaluation of alternatives. Overall, West Fork was able to meet objective of higher returns from the forest while simultaneously demonstrating improvement in dispersal habitat over the next four decades.

Forest Management Plan Implementation: The Economic Implications of Straying from the Optimal Strategy (2005)
Bruce L. Carroll, Eric S. Cox and Ian Prior
Optimization modeling techniques are gaining in popularity because they allow the exploration of management alternatives and provide an optimal solution. As investor sophistication grows models incorporate more and more detailed geographic information system (GIS) data, inventory data, and biometric assumptions.To examine the sensitivity of financial returns, three common forest management planimplementation methods were investigated. It is shown that varying from the optimal plan can have significant con-sequences in future volumes, revenues and net present value.

Thinning Guidelines for Loblolly Pine Plantations in Eastern Texas based on Alternative Management Criteria (2004)
Charles T. Stiff and William. F. Stansfield
Separate thinning guidelines were developed for maximizing land expectation value (LEV), present net worth (PNW), and total sawlog yield (TSY) of existing and future loblolly pine (Pinus taeda L.) plantations in eastern Texas. The guidelines were created using data from simulated stands which were thinned one time during their rotation using a combination row (20 percent) and selection thin to achieve a residual stocking target. LEV for future stands which had been thinned indicated optimal rotation ages of 20, 24, 28, and 32 yrs for site index 85, 75, 65, and 55 ft, respectively. For existing stands at optimal
rotation age, PNW increases with both thinning age and site index. However, for future stands at optimal rotation age, LEV reaches maximum values at thinning ages that vary by site index. TSY reached maximum values at residual stocking levels, which increase with increasing site index for both existing and future stands. Marginal analyses indicated that when thinning older stands of poorer site quality, economic criteria (PNW or LEV) increased with higher initial stocking, and total sawlog yield (TSY) decreased with lower initial stocking. Regression tree analysis used thinning age and residual stocking for predicting PNW, LEV, and TSY by initial stand attributes (site index, and initial stand age and stocking). Thinning guidelines were derived from the tree-based models. A 4-step procedure is provided for applying the guidelines.

Short-Term Harvest Schedule Sensitivity to Future Stumpage Price Assumptions (2003)
Eric S. Cox
Forest planning models have long been used as an analytical tool for providing information to facilitate effective decision making and planning. Inherent to the financial analyses conducted with these models are assumptions concerning key financial parameters contained in the model such as discount rates, future costs, and future stumpage prices. While projecting timber prices into the future with any accuracy is an extremely difficult exercise, price forecasting is nonetheless a critical part of forest planning analyses. The ramifications of these assumptions over a long planning horizon can be significantly different product flows, activity levels, and cash flows. The purpose of this study is to investigate the impact of different future stumpage price assumptions on the short-term (5-year) timber harvest schedule for a southern pine forest, and to examine how much of the schedule is financially driven. The findings indicate that the short-term harvest schedule is sensitive to different price projections. This result is significant especially with respect to the timing of short-term timber harvest decisions to take advantage of market prices.

Applying Modern Portfolio Theory to Timberland Allocation (2003)
Bruce L. Carroll
Significant research has gone into developing models showing the appropriate mix of equity investments to optimize risk-adjusted returns. These optimal portfolios often have a mix of stocks, bonds, and cash. Due to low correlation between timberland investments and equity investments, timberland has a high probability of success in improving portfolio risk adjusted returns. To gain insight into this issue, a Markowitz portfolio optimization technique was used to calculate the optimal mix of timber investments across geographies when mixed with traditional investments.

Spatial forest planning: where did all the wood go? (2002)
Karl R. Walters and Andrew Cogswell
Spatial forest planning has become a hot topic in recent years. By and large, the problems associated with spatial planning tend to be drive by economic, social and political requirements. In this paper we examine three different spatial issues and their impacts on management objectives.

An Empirical Evaluation of Spatial Restrictions in Industrial Harvest Scheduling: The SFI Planning Problem (2001)
Karl R. Walters and Eric S. Cox
A commercially available hierarchical planning software suite is used to analyze the impact of the adjacency and harvest size objectives within SFI on a representative forest of the U.S. Southeast. Ten alternative, spatially feasible tactical schedules were developed for a 15 yr planning horizon and achieved 73.4 to 75.6% of the harvest volume predicted by the nonspatial strategic harvest schedule.

Spatial Forest Planning On Industrial Land: A Problem in Combinatorial Optimization (1997)
Karl R. Walters
Foresters face difficulties not only in scheduling harvest blocks, but even in delineating them in the presence of spatial restrictions. The spatial forest-planning problem (SFPP) involves simultaneous allocation and scheduling of cells to form harvest blocks that meet adjacency, greenup and opening-size constraints. A preliminary investigation of simulated annealing and tabu search was made to test their suitability to the SFPP. Simulated annealing yielded better solutions and shorter execution times for a number of contrived but otherwise representative problems.

Spatial and temporal allocation of stratum-based harvest schedules (1991)
Mark S. Jamnick and Karl R. Walters
Stratum-based timber harvest schedules must be disaggregated into operational plans prior to implementation. In most cases this is an expensive and time-consuming manual task that does not ensure consistency between the long-term harvest schedule and short-term operational activities. This paper presents the results of applying the CRYSTAL algorithm, which automates the disaggregation and allocation of a stratum-based harvest schedule into blocks, to a small forest in New Brunswick.

White Papers

Financial Performance of Loblolly and Longleaf Pine Plantations (2008)
Steven D. Mills and Charles T. Stiff
The financial performance of selected management regimes for loblolly and longleaf pine plantations were compared for four cases, each with low and high site productivity levels and each evaluated using 5% and 7% real discount rates. In all cases, longleaf pine was considered both with and without pine straw harvesting as part of the management regime. Results indicate that longleaf pine regimes that do not incorporate pine straw raking yield financial results that are inferior to those from intensive loblolly management. However, with the addition of pine straw revenues, longleaf management can yield returns that are comparable to typical loblolly pine regimes (-16% to +3%, depending on site quality and discount rate). With little to no direct return on reforestation investments before 20-25 years longleaf pine may be a more attractive alternative, due to lower establishment costs up front and favorable LEV comparisons.


Barber Revisited: Aggregate Analysis in Harvest Schedule Models (2009)
Steven D. Mills, Bruce L. Carroll & Karl R. Walters
We revisit Barber's paper on aggregate analysis to determine if the recommendations made in the original paper still make sense in the context of an optimization-based analysis, rather than the binary-search/inventory projection methodology employed by Barber originally.

Error progation in forest planning models (2006)
Karl R. Walters & Sean J. Canavan
We evaulate the impact of measurement error on three components of a forest planning model: initial inventory, first period harvest and silvicultural activities chosen. Calculated initial inventory was off by as much as 15%, and significantly different objective function values and activity schedule also resulted.

Forest Structure & Spatial Restrictions: Interactions & How They Affect Harvest Goal Achievement (2003)
Karl R. Walters
This presentation investigates the role of forest structure in limiting the achievement of harvest and/or revenue goals of forest management. Results show that some spatial arrangements of stands suffer much greater reductions in goal achievement than others. Some means of ameliorating the reductions is also given.