Applying Theory of Constraints to Timber Harvesting

Matthew C Kelly,René H Germain

doi:10.5552/crojfe.2020.534

Abstract

Logging firms are a critical link in wood supply chains, connecting forest landowners with markets for wood products. Improving operational planning can benefit individual logging firms as well as the larger wood supply chain in which they operate. Applying concepts from Theory of Constraints (TOC) to timber harvesting may help achieve greater predictability and efficiency when planning harvest operations. However, examples that demonstrate how TOC can improve logging operations are lacking. This study focuses on the analysis of production and activity data collected during the harvest of a temperate mixed hardwood forest in the Northeast United States using a chainsaw-forwarder system through a TOC lens. Specifically, the drum-buffer-rope (DBR) method was used to reschedule operator and machine activities such that a consistent flow of wood from stump to landing was maintained despite anticipated production setbacks. The results of this case study provide insights into the usefulness of applying TOC to logging operations. In particular, logging businesses must be able to estimate machine and operator productivity within a given harvest context to identify and exploit system constraints, while taking full advantage of unused capacity of any non-constraint functions.

Highlights

In recent decades, various operations management philosophies have emerged that seek to transform how organizations manage their internal processes to improve operational efficiency and effectiveness
It is important to note that the scheduling technique demonstrated here is just one component of the larger Theory of Constraints (TOC) philosophy and that the value of TOC is that it provides a framework for problem solving (Luebbe and Finch 1992)
Few examples exist that illustrate just how TOC concepts can be applied in this context

Summary

Introduction

Various operations management philosophies have emerged that seek to transform how organizations manage their internal processes to improve operational efficiency and effectiveness. These philosophies focus on concepts such as waste elimination, system-based thinking, and continuous improvement. Among these philosophies, one of the most prominent is the Theory of Constraints (TOC) (Goldratt and Cox 2004). Applying TOC involves the following five focusing steps: (1) identify the constraint in the system (2) decide how to exploit this constraint (3) subordinate everything else to the above decision (4) evaluate and improve the system’s constraint (5) if improvement of the constraint leads to a new constraint in the system, go back to step 1 (Stein 1997, Rahman 1998, Goldratt and Cox 2004, Noar et al 2013)

Objectives

Methods

Discussion

Conclusion