Review Reports - Wind and Snow Loading of Balsam Fir during a Canadian Winter: A Pioneer Study

Round 1

Reviewer 1 Report

This manuscript presents the results from a comprehensive and novel study examining the impact of seasonal differences (presence or absence of snow) on the mechanical behaviour of balsam fir.

The study design is sound and the paper is generally well written. However, it requires some editing to improve the presentation before it can be published. I found the description of statistical models a little difficult to follow, partly I suspect because the terminology used to describe the models isn't quite correct. For example a log link function (line 198) is used in generalised linear models, whereas the models presented here simply have the response variable transformed to a logarithmic scale so that they are log-linear models. Secondly, I was confused as to whether these are mixed effects models. The use of the terms "fixed" and "random" effects would suggest this is the case, but I couldn't see how the random effects were generated. I would suggest seeking input from a statistician to resolve the description of the models as it is a key component of the paper.

The paper also requires some editing to tighten up the writing. In some cases the writing style is arguably too conversational for a peer-reviewed journal. The use of terms such as "interesting" and "idea" should be avoided. The hypotheses that are presented on lines 78-86 also need to be phrased as hypotheses, rather than as statements. If they are competing hypotheses then this should be made clear. There are also a number of typos and grammatical errors throughout the paper that need to be corrected. I haven't listed these in the review, but they should be readily apparent with a careful read through the paper

Author Response

"This manuscript presents the results from a comprehensive and novel study examining the impact of seasonal differences (presence or absence of snow) on the mechanical behaviour of balsam fir. The study design is sound and the paper is generally well written. However, it requires some editing to improve the presentation before it can be published."

Thank you for reviewing our paper and for your comments.

"I found the description of statistical models a little difficult to follow, partly I suspect because the terminology used to describe the models isn't quite correct. For example a log link function (line 198) is used in generalised linear models, whereas the models presented here simply have the response variable transformed to a logarithmic scale so that they are log-linear models. Secondly, I was confused as to whether these are mixed effects models. The use of the terms "fixed" and "random" effects would suggest this is the case, but I couldn't see how the random effects were generated. I would suggest seeking input from a statistician to resolve the description of the models as it is a key component of the paper. "

We agree. Following your remarks, we made the appropriate changes with the help of a statistician colleague. We hope this version will be clearer for the readers.
L.198: “The response variable (Mmax, Nm) was log-transformed prior to the analyses to linearize the relation between it and our explanatory variables and to meet the assumptions of homoscedasticity and normality of the residuals.
L.209: “To consider repeated measurements among trees, tree was included as a random intercept in our models. We also included random slopes for ws and Snow as the effect of these two variables on Mmax could potentially vary among trees.”
L.257 and L.283, “log-linear model” replaced by “mixed linear model”.

"The paper also requires some editing to tighten up the writing. In some cases the writing style is arguably too conversational for a peer-reviewed journal. The use of terms such as "interesting" and "idea" should be avoided."

L.159 relevant (instead of interesting)
L.368 useful (instead of interesting)
L.334 fact (instead of idea)
We have carefully edited the paper to try to tighten up the language at several points.

"The hypotheses that are presented on lines 78-86 also need to be phrased as hypotheses, rather than as statements. If they are competing hypotheses then this should be made clear."

The first hypothesis deals only with winter data whereas the second one includes both seasons. This has been made clearer in the statement of the first hypothesis. Since they are not using the same data set, they are not competing hypothesis. One relates to the added load, the other one includes both the temperature effect and the added load.
We have added a sentence after the hypotheses to explain more clearly that they are not competing hypotheses

"There are also a number of typos and grammatical errors throughout the paper that need to be corrected. I haven't listed these in the review, but they should be readily apparent with a careful read through the paper"

Paper has been edited more carefully

Additionnal corrections:

Also : we have reviewed our analyses following the suspicion of errors and the variable selected in the second model is now C12 (instead of DBH²H), we have included all the necessary changes regarding this new model. The "general" results have not changed at all. Sorry about this.

We have also added an appendix with the competition indices and the link to the data (to be updated soon on the website).

Reviewer 2 Report

The paper seems to be really "pioneer" work in this topic as described by authors. Although it is not the first analyse of interactions "snow-wind", however the first time it is based on such detailed measurements on ground. Before the final publication it needs some corrections to make it fully understandable for readers:

Chapter 2, Table 1 - line 104 (descriptions) - there is no clearly described relations between CIB and C_BAL. Readers are referred to the position [36] to find the definition of the competition index but in this article (Saad et al. 2017) I couldn't find any competition indices.

Few positions in the list of references require to be completed: [20], [21] and [35].

Author Response

"The paper seems to be really "pioneer" work in this topic as described by authors. Although it is not the first analyse of interactions "snow-wind", however the first time it is based on such detailed measurements on ground."

Thank you for reviewing our paper and for your comments.

"Before the final publication it needs some corrections to make it fully understandable for readers: Chapter 2, Table 1 - line 104 (descriptions) - there is no clearly described relations between CIB and C_BAL"

The definition of CIB and relationship to C_BAL is given in the legend for Table 1. It is the ratio of C_BAL to BA. We also now describe this in the text.

"Readers are referred to the position [36] to find the definition of the competition index but in this article (Saad et al. 2017) I couldn't find any competition indices"

Sorry for the mistake, the reference should have been: Biging, G.S.; Dobbertin, M. Evaluation of Competition Indices in Individual Tree Growth Models. Forest Science 1995, 41, 360–377. Apparently a lot of references were misplaced when the Journal decided to put the tables within the text (they were originally at the end of the text). Everything is back to normal now. A big thank you for pointing it out!

"Few positions in the list of references require to be completed: [20], [21] and [35]"

[20] Wickham: we added the website link
[21] is a website, this reference already respect the MDPI standard for website, see their section ”Back matter – references” https://www.mdpi.com/journal/forests/instructions.
[35] now [39] we do not have more information about this reference.

Additionnal corrections:

We have also added an appendix with the competition indices and the link to the data (to be updated soon on the website).