Benefits and Requirements of Mathematical Optimization in the Allocation of Wood to a Network of Forest Product Mills

Round 1

Reviewer 1 Report

The manuscript under review compares manual timber supply planning for five sawmills against optimization tools, which can be used to solved the same tasks.

The introduction is sufficient enough to understand the ambitions behind the study. The goals i to iii are clear and interesting. The literature review falls short, but covers some important works in this field.

Materials and Methods provides a basic overview on the optimization model and the defined scenarios. However, it would be interesting to have more details on the size of the planning problem like the number of harvesting units, volumes to move, demand per mill, transport and harvesting costs.

The results indicate that the usage of optimization tools lead to increased net value and decrease planning efforts. The results seem to be reasonable and the presentation of the different scenarios is interesting. Figure 4 to 6 require improvements, as the y-axes are not labeled properly and values above the bars show to many digits and the wrong decimal separator. For me the bar charts seem to be not appropriate here. I think the figures 4 to 6 can be replace with a table showing the savings.

The allocation of the harvest blocks differs largely between manual and optimal scenarios. Does manual planning also account for seasonal variations like accessibility?

If I read the optimization model LogiLab correctly limited availability of harvest units in specific time periods can be considered. Are there any limitations in terms of access to the harvest units in the study area?

Beside these minor points raised, the manuscript is interesting to read and deserves a publication after addressing above mentioned points within a revision.

Author Response

Attached is pdf file of our response and the revised manuscript. 

Author Response File: Author Response.pdf

Reviewer 2 Report

The authors wrote an interesting paper on an interesting topic of supply chain management and optimization. The paper is well-written overall and presents a complex assessment of the deployment of timber supply chain optimization models in Quebec companies. Language-wise, I recommend moderate English editing, e.g., the use of the term "timber" instead of "wood" in cases when the merchantable commodity is referenced and not the substance. Furthermore, the authors need to be more meticulous in their use of past tense in reference to their own research (e.g., L161-164).   

Within the Literature review or Introduction, I recommend including information on the goals of the optimization of logistic systems and their effects on how the systems are then set up (e.g., optimizing for minimal unit costs of transport will result in a different setup of the supply chain than optimizing for shortest distance or time). In the Methods section, the authors should provide information on how the costs of the current planning method were calculated. They only note that the current method is more time-consuming (section 4.1), but do not provide any further explanation as to why or how the time consumption was measured or determined. Another point is that Figures in Section 4 should be side-by-side, not one sub-figure below another. 

Other than the remarks mentioned, I think the paper is well-written and provides interesting information for the readers. I recommend publishing it after implementing the remarks. 

Author Response

See pdf file for response to comments and revised manuscript

Author Response File: Author Response.pdf