HW Buck and Optimal Hardwood Bucking
Bucking hardwood stems into the optimal combination of logs is a difficult task given the complexity of grading systems and log defects. Even seasoned graders and buckers often disagree about where cuts should be made in a given stem in order to obtain the most value from the stem. The Hardwood Research Group at Michigan Technological University's (MTU) School of Forest Resources and Environmental Science has worked extensively in the northern hardwood region to develop and implement optimal buck technologies. Recent efforts have focused on developing a comprehensive log bucker training program to improve the value recovery when bucking hardwood logs. A study involving Menominee Tribal Enterprises, the Wood Education Resource Center (WERC) of the Forest Service, and the Hardwood Research Group at MTU used a complete package of bucker training, including the use of HW Buck, to increase value recovered by an average of 31%. Bucker training to improve value recovery includes three critical skills which buckers must master to cut more valuable logs:
Defect identification on the surface of hardwood stems and the internal problems associated with those defects.
An overview of grading and scaling, including the importance of defects.
Strategies to improve profitability by making bucking decisions that produce more valuable logs.
All training components blend in-the-field exercises, presentations, and indoor activities.
Trainees see the optimized solutions given by HW Buck and can compare them to their own field selection of bucking cuts on the sample tree stems. When Buckers first use the program the optimal bucking pattern calculated by HW Buck includes a dramatic shift up in log grade and also recovers more net scaled volume of the stems by reducing sweep. This increase in scaled volume occurs even though the software identifies more cull material; scale deductions due to sweep are greatly reduced. With practice, buckers improve their skills and improve the value recovery in the logs they buck.
The Future of Hardwood Bucker Training - the H VIP Project
The 31% increase in gross sawlog and veneer value observed in the MTE study represents an enormous potential benefit for the hardwood industry. To help make these potential gains a reality for the hardwood industry, the Hardwood Value Improvement Project is delivering training to local experts, who will then deliver the training to log buckers across the hardwood region. This program is offered by the Ohio Forestry Association with technical and training support by the Hardwood Group at MTU and Noble Forestry and with financial and logistical support from WERC.
HW Buck - The Basics
HW Buck is a computer program - and in many ways a computer game - which bucks hardwood logs and challenges buckers to improve their skills. HW Buck is the only software package capable of user friendly computer simulation of hardwood bucking and simultaneous determination of the optimal bucking pattern for a hardwood tree stem. The program is designed to run in Windows and, with over a decade of development work, contains the flexibility to allow users to modify many parameters to match their own local situations. HW Buck runs on most PCs.
HW Buck uses data from actual hardwood tree stems to generate a virtual tree stem. The stem is reconstructed as a computer model for analysis and displayed on the computer screen for users to examine. The true innovation of HW Buck is its ability to grade and scale logs which are cut from the virtual tree stem and to determine the optimal bucking pattern which gives the greatest possible financial value from the stem. HW Buck has been set up to operate in a game-like fashion in which the user bucks up a stem and compares produced results to those of the optimal bucking pattern. While users may enter data from their own trees, HW Buck comes with a set of 150 trees prepackaged and ready for use.
HW Buck - The Details
HW Buck allows trainees to test their skills as a group or to compare their work with an optimal solution. The cumulative effort of working on several logs can also be retained with the tracking option. The game's learning environment can be modified to suit the needs of the training group.
HW Buck comes with several data sets for sawlog and veneer grading rules, roundwood products, prices, and log rules. This information is brought together to create a market and can be modified to mimic local markets throughout the hardwood region. Combined with the 150 tree database stored within HW Buck, trainees encounter a wide range of bucking situations.
Users are given a tree which includes defects. (In HW Buck on-site training sessions, defect identification and the impact of defects on log grades are emphasized.) In the stem in shown below the magenta ovals represent defects on the surface of the log.
Trainees can rotate the stem to find other defects, including interior defects such as stain, heart, and decay.
After observing defects and stem shape, trainees then select where they feel the bucking cuts are best located to maximize financial returns. The same tree is shown below, with two suboptimal cuts.
Often the trainee decides to use one of the game modes which displays the best set of cuts and compares the trainee's cuts to the optimal cuts. The final screen, like the one shown below, shows the differences between the bucker's choices and the optimal selection. Details of sawlog grade and size, sweep, volume lost to sweep (S) and cull (C), total volume in board feet and value are displayed for each log.
HW Buck Flexibility - How You Can Make HW Buck Work for You
While HW Buck comes with a substantial range of built-in features, the software also allows users to add their own trees and to modify grading rules, types of roundwood products, prices, and log rules to create markets to match the user's local situation.
These options are available in the game menu of the main page. Users can view the current data used in HW Buck or define a new set of data which matches the local hardwood product market.
HW Buck allows users to change prices.
Special products which may be locally important, or important only to a single mill, can be added to HW Buck. The specification need not be for a veneer grade. HW Buck accepts a range of product types and allows the user to define the product right down to details of length, diameter, sweep, and defects and their location on the log. This local-level specification allows training to match local conditions and maximize value recovery for the user's own immediate needs.
HW Buck - One Part of Comprehensive Bucker Training
A good bucker knows defects in the field and how those defects are important in log grading. H VIP training includes this critical information in addition to use of the HW Buck program. There is no substitute for this type of knowledge. However, bucking hardwood stems is a complex task and even the best can benefit from the repeated, analytical training and information provided by HW Buck. Our work with Menominee Tribal Enterprises shows that buckers can improve returns by an average of 31% when trained with HW Buck. Profits increase when buckers know how to combine the skill, the art and the science of bucking in the woods.
You may obtain a demonstration version from our download page.
If you are interested in improved value recovery in your hardwood operation, contact Jim Pickens (906) 487-2218 or jpickens@mtu.edu] for more information on Hardwood Bucking Training.
Optimal Bucking Pattern: Hardwood tree stems are manufactured by buckers into logs of varying qualities (grades) and values. The location of cuts (or pattern) along the stem determines the specific set of logs produced. Different patterns produce sets of logs with different qualities (grades) and values. There are thousands of potential patterns on any given stem. Each pattern generates a different sum value for all the logs generated by that cutting pattern. The optimal bucking pattern is that cutting pattern which generates the highest possible sum value of logs. (back to the main text)
Value Recovery: The sum value of logs produced on a given hardwood tree stem by a given pattern of cuts as compared to the value of the optimal bucking pattern. Value recovery can only be meaningfully discussed when the optimal value possible can be determined. HW Buck determines this optimal value. Similarly, value recovery may be described as the amount of value produced for a bucking pattern for a stem as compared to the maximum value possible. (back to the main text).
Page created: August 7, 2006.
Last updated:
September 25, 2006
