**5. Conclusions**

The current study found that the panel hacksaw method was temporarily applied to collect resin intensively from pine trees under Japanese rule, and after the Korean war, the conventional chisel method was again applied to collect resin until the middle of the 1970s for livelihood. For resin collection, red pines thicker than 20.0 cm were used. The wounds created by the conventional chisel were found to be healed, whereas the ones created via the panel hacksaw method still required long times for healing. From the large wounds, a benefit is that a large amount of resin can be obtained, but these wounds take a long time to heal completely. On the other hand, the traditional chisel method offers a sustainable supply of resin and rapid healing of the wounds. Therefore, we can conclude that the traditional method to obtain non-timber forest products will be a remarkable reference to determine forest policy on the usage of forest resources sustainably and should be passed from generation to generation in Korea.

**Author Contributions:** Designing the study, analyzing the data and writing the paper, E.-B.C.; Designing the study and supporting the writing of the manuscript related to resin collection history, C.-R.P.; Designing the study, analyzing the data and supporting the writing of the manuscript, J.-W.S.; Measuring the ring widths and cross-dating the tree-ring time series, Y.-J.K.; Sampling in the field and preparation of the samples for the ring-width measurement, J.-H.P. All authors have read and agreed to the published version of the manuscript.

**Funding:** This study was funded by the National Institute of Forest Science of Korea, grant number NIFOS FE 0100-2017-05.

**Conflicts of Interest:** The authors declare no conflict of interest.
