Branch Elongation, Bud Durability, and Wind-Generated Crown Movement Associated with Crown Abrasion in Deciduous Trees

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors Here are most important ones for Editor. First research was done in 2010-2012. It makes some questions why authors waited so long. Further authors analyze three techniques that were investigated to evaluate the process of crown abrasion and potential impacts of crown abrasion on stand development. Surprisingly, but the number of tree species investigated as well as samples is different. Also, the amount of samples seems insufficient for me.

Also, I do lack combined analysis in results or at least in discussion part.

 

Comments for author File: Comments.pdf

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This research quantifies the impacts of crown abrasion between neighboring trees for several deciduous species to study how crown abrasion may influence stand dynamics. Tree interactions were evaluated during the dormant and growing season to determine how wind-generated movement affects crowns under foliated and un-foliated conditions.

 

This research in interesting but some aspects should be changed

 

line 50

"The purpose of this research is to examine how crown abrasion might occur among different hardwood species, with a focus on branch elongation, bud durability, and force estimates from branch acceleration causing bud break during wind events."

2 working hypotheses should be specified.

 

line 70

" Movement of a tree crown depends on the extent of static and dynamic strain created by the wind disturbance as well as diameter and mass of the tree branch which varies by species. Dynamic strain is dependent on pressure from gusts of wind and the frequency of branch oscillation in the crown. Oscillation frequency of broad-leaf trees is seasonal whether trees are with or without leaves."

A very clear idea - any continuous mechanical system has a series of natural oscillation frequencies at which it oscillates under the action of external forces (see Waves (Berkeley Physics Course, Vol. 3 by Frank S. Crawford Jr.)

 

line 91

"The research was conducted during 2010-2012 at three separate locations, each incorporating different stages of the study". The study period being quite old, perhaps the study should have been resumed with more sensitive equipment.

 

Table 1.

Platanus occidentalis - no records - should be removed.

 

line 207

"The research study only had resources to monitor sway of one tree with four accelerometers, an anemometer, and recording devices due to the irregularity of wind events (unknown time periods) during the growing and dormant seasons"

what is the type of accelerometer. - some specifications should be presented! Doesn't connecting a device somehow change the dynamics of the system?

 

line 214

"Branches at least six meters long in each cardinal direction were selected and accelerometers were attached 0.6 meters from the end of the branches to ensure that the weight of the device had minimal influence on branch movement"

I think that this hypothesis is not sufficient, the movement of the tips of the branches may be different in the case of collisions between the branches.

 

line 231

"Top wind gust speeds were divided into categories: 0 to 8.1, 8.2 to 16.1, 16.2 to 24.1, 231 24.2 to 32.2, 32.3 to 40.2, 40.3 to 48.3, 48.4 to 56.3 and 56.4 to 64.4 KPH." - What does kph mean?

 

line 234

"The accelerometer data were analyzed using mixed model analysis of variance" ANOVA was performed in relation to which parameters?

 

line 250

"Forces in Newton (N) were calculated to address the possibility of abrasion. Joules recorded from the pendulum impact tester are units of work and cannot be used to calculate the minimal force required for bud failure. The drop height of the pendulum was 61cm and was used to calculate minimal force by applying the equation F=U * 0.6069m where F is the force and U is the energy."

This aspect is very interesting: Force [measured in Newton] is given by a product of U-Energy [measured in Joule=N*m] and a distance [measured in m]. A reference should certainly be given for this relationship!

 

figures 1-4 show raw results - without adequate statistical or numerical processing

 

The conclusions of the article

I think this section should be reformulated.

 

Author Response

File Attached

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Dear Authors,

Thank you for your answers.

Regards