1. Loggers' Perception and Cut-Block Design
Peter Schiess and Dean Berg
Forest Engineering
University of Washington

2. Problem
Setting Design is the fundamental basis for timber harvest and efficiency of operation
Logging production/costs depend on
cut-block layout & site characteristics
Interaction of design attributes is difficult to measure

3. The Problem: How Do You Compare the Relative Efficiency of Different Settings ? It’s Not just a Clearcut Anymore!!

4. The Past: Time-motion studies are site specific
The Past: Time-motion studies are site specific. Extrapolation to other conditions are questionable.

5. Logging operations are under severe environmental constraints
No clear understanding of interaction among design variables
Engineers still learning about Structural Retention (STR)
Harvest systems with STR involve two principal costs
-foregone timber revenue
-increased harvesting costs

6. Structural Retention Aggregated Retention Dispersed Retention
Structural Retention is being broadly implemented with little experience on cost and cut-block layout

7. Interaction of Setting Design Parameters and Human Factors (Perceptions)
Borrow from Market Research Technology
Evaluate perceptual mapping of loggers through market research
Use the above information to develop utility values for setting design

8. Methodes
Pilot study - survey of logging engineers, identified initial 108 cost variables
Construct initial survey with 20 variables
Use of focus groups to establish critical factors of setting design and to develop questionnaire - 14 variables
Use of interviews and questionnaires, 480 loggers polled, with 120 returns
Factor analysis and conjoint study
Follow-up with interviews

9. Harvest Cost Variables as Identified by Loggers for Three Silvicultural Systems and two Harvest Systems
Harvest Cost Variables
Cable System
Ground-based System
Silvicultural systems
Clearcut
Aggregated STR
Dispersed STR

10. The 14 harvest cost variables as identified by loggers for three silvicultural systems and two harvest systems
Size of Timber (average scaling diameter
Payload (pieces/turn
Total Harvest Volume
Topography (from even to broken)
Slope
Yarding Distance ( ft)
Yarding Distance (>1000 ft)
Stand Density (Trees/acre)
Uphill Yarding
Downhill Yarding
Equipment (types & amount)
Labor (Demand)
Skill (Experience and Education
Haul Distance (from Landing to Mill)

11. Utility Values for Yarding Distance and Direction

12. Utility Values for Three Silvicultural Systems

13. Application of the Study to a Cut-Block Design
Utility values can be transformed into design criteria
Cut-Blocks can be compared on a quantitative basis
The relative merit of one design over another can be evaluated

14. Applying the Utility Values to Three Cable Settings

15. The Setting Utility for Three Cable Settings for a Clearcut Scenario

16. Applying the Utility Values to Three Cable Settings

17. Comparing Three Clearcut Units

18. Comparing Three Cable Units with Different Silvicultural Systems

19. Conclusions
Market Research Technology is an Important Tool to Bring Psychometric Data into the Forest Engineering Field
Through Market Research, Human Factors can be Brought into the Cut-Block Design - Loggers’ Perceptions about Cut-Block Layout

20. Conclusions
Loggers’ Perception about Cut-Block Layout is an important Step in Understanding the Implications of Alternative Silvicultural Systems on Harvest Costs and Productivity