• Journal of Korean Society of Forest Science
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• v.110 no.2
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• pp.155-164
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• 2021

Many studies have been conducted on developing automatic plant identification algorithms using machine learning to various plant features, such as leaves and flowers. Unlike other plant characteristics, barks show only little change regardless of the season and are maintained for a long period. Nevertheless, barks show a complex shape with a large variation depending on the environment, and there are insufficient materials that can be utilized to train algorithms. Here, in addition to the previously published bark image dataset, BarkNet v.1.0, images of barks were collected, and a dataset consisting of 53 tree species that can be easily observed in Korea was presented. A convolutional neural network (CNN) was trained and tested on the dataset, and the factors that interfere with the model's performance were identified. For CNN architecture, VGG-16 and 19 were utilized. As a result, VGG-16 achieved 90.41% and VGG-19 achieved 92.62% accuracy. When tested on new tree images that do not exist in the original dataset but belong to the same genus or family, it was confirmed that more than 80% of cases were successfully identified as the same genus or family. Meanwhile, it was found that the model tended to misclassify when there were distracting features in the image, including leaves, mosses, and knots. In these cases, we propose that random cropping and classification by majority votes are valid for improving possible errors in training and inferences.

• Journal of the Korean Wood Science and Technology
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• v.7 no.1
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• pp.3-7
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• 1979

A bark comprises about 10 to 20 percents of a typical log by volume, and is generally considered as an unwanted residue rather than a potentially valuable resources. As the world has been confronted with decreasing forest resources, natural resources pressure dictate that a bark should be a raw material instead of a waste. The utilization of the largely wasted bark of genus Pinus, Quercus and Populus grown in korea can be enhanced by Knowing its chemical Properties. Specially, uses of bark in mulching, growing media and soil amendment can be enhanced by knowing pH and C.E.C values. In this paper, an investigative study is carried out on the pH-and C.E.C-values. The results may be summarized as follows: 1. Bark is acid in nature, and pH values of bark varying from 3.3 to 4.7, is lower than that of wood.pH value of Pinus is the lowest. 2. Cation exchange capacity of bark is greater than that of wood, silt loam soil, and wheat straw.CEC of bark is 45.7 meq/100gm in Pinus, 41.8 meq/100gm in populus, 37.8 meq/100gm in Quercus.

• Current Research on Agriculture and Life Sciences
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• v.11
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• pp.25-30
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• 1993

The buds of Hayward/Bruno tree were damaged from $-7^{\circ}C$ but serious damage was found on the buds treated at $-15^{\circ}C$ and $19^{\circ}C$. The bark tissue was more suceptible to low temperature than the bud. The trees were survived and bursted their at all on the top of the graft union and new shoots were formed from the rootstock of the tree. Yellowish area on the leaf surface was found, which is believed that as a result of low temperature. From these, the kiwifruit trees must be grafted with cold tolerant rootstocks will be clarified in future.

• Journal of the Korean Wood Science and Technology
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• v.34 no.6
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• pp.12-20
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• 2006

The objectives of this study were to identify the species of coffin woods excavated at Ma-jeon relic in Jeonju and to date this coffin using tree-ring method. Al coffin woods were identified as red pines, most possibly, Pinus densiflora S. et Z. Tree-ring dating provides a calender year to each ring and produces the cutting date, if the bark presents. Due to the presence of bark and complete latewood present, the cutting date of the tree for coffin turned out between A.D. 1637 autumn and 1638 spring. However, due to the seasoning and storage periods, actual coffin manufacturing and burial time may be a little different from the tree-ring date.

• Journal of Korean Society of Forest Science
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• v.98 no.5
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• pp.584-592
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• 2009

The objective of this study was to examine the impact of pruning intensity on the vigor and cambial growth of the treated trees, and on the closure of pruning wounds for one year after pruning treatment. Two tree species, Pinus strobus and Acer palmatum, planted broadly in the urban forest of Korea were selected for the experiment. Intensity of pruning, which was estimated by proportion of removed branches, was categorized into five levels with about 10% intervals from lowest 8% up to 46%. Following parameters were examined; cambial electrical resistance (CER) and the cambial growth of trunk at 30 cm above the ground for the years before and after pruning, the cambial growth of stem at 1.5 cm above the branch bark ridge (BBR) of the pruned branch, and closure of pruning wound for one year after pruning. Tree vigor inferred from CER had a tendency to be weakened as pruning intensity increased in P. strobus, while that of A. palmatum was not affected. The trunk growth decreased significantly when the pruning intensity was higher than 30% in both species. The closure of individual pruning wound was related more to the cambial growth of stem at 1.5 cm above BBR than to the pruning intensity. Comparing the closure rate of pruning wound for one year, P. strobus with 72.1% was faster than A. palmatum with 39.3%, which corresponded with the rate of cambial growth of the two species.

• KSBB Journal
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• v.9 no.3
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• pp.299-305
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• 1994

Taxol contents in various parts of 15 years old yew tree were determined. The descending order of taxol content per unit mass was stem bark, root bark, needle and seed. In the seed, that order was seed coat, embryo and endosperm. The total amount of taxol extractable from a 15 years old yew tree was 1.68 gram. This amount was distributed in needle, stem bark, root bark and seeds as 48.0, 23.8, 27.9 and 0.4%, respectively. Altitudinal variation of taxol content was also observed. More taxol was observed in yew trees grown at high altitude over 1000m above sea level. Calli and suspension cultures were induced from various yew trees. The presence of taxo] in cultured cells was established bv HPLC. The taxol content in cultured cells were different according to the source of explants. These results may be useful for the goal of large scale taxol production by cultured yew tree cells.

• Journal of the Korean Wood Science and Technology
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• v.45 no.3
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• pp.317-326
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• 2017

The wood and bark of Hawthorn tree (Crataegus pinnatifida Bunge) were immersed with 70% aqueous acetone for 3 days. After filtering, the wood extracts were fractionated with n-hexane, chloroform ($CHCl_3$), n-butanol (n-BuOH) and $H_2O$, and the bark extracts were fractionated with n-hexane, $CHCl_3$, ethylacetate (EtOAc) and $H_2O$. Then antioxidative and anti-inflammatory activities were evaluated on each fraction. Antioxidative activity indicated high activity in the n-butanol soluble fraction of wood and in the EtOAc soluble fraction of bark. Especially, the EtOAc soluble fraction of bark showed much higher antioxidative value compared to the controls, buthylated hydroxytoluene (BHT) and ${\alpha}$-tocopherol. In the anti-inflammatory activity, all of the tested fractions except the $H_2O$ soluble fraction of wood showed high inhibitory effect on nitric oxide (NO) production. Based on the above results, the extracts of hawthorn tree may be applied for one of the natural biomass sources that can be used as an antioxidant and an anti-inflammatory substance.

• Journal of Plant Biotechnology
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• v.29 no.3
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• pp.209-215
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• 2002

Four kinds of kalosaponins from inner bark of Kalopanax pictus Nakai as a medicinal and edible timber tree species growing in Korea was analyzed by HPLC. A considerable range of variation in the contents was observed among population. The kalosaponins contents in inner bark from each population were the highest in the Mt. Barwang (30.37 mg/g on the dry weight basis) followed by Mt. Gariwang, Hanra II, Mangun, Paltan, and Hanra II population. Growth factors that might have influenced the contents of the kalosaponins were also examined. As both analysis results of partial correlation and multiple regression, the weight of inner bark and tree age were influenced the kalosaponin O contents. The kalosaponin B contents was influenced by both the weight of inner layer bark and annual mean DBH increment. The contents of kalosaponins appeared to be closely related to the inner bark characteristics.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.12
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• pp.1257-1269
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• 2012

The dyeing behaviors of berberine chloride, palmatine chloride hydrate, and Phellodendron bark extract on silk fabric were investigated to evaluate palmatine as another chromophoric substance of Phellodendron bark. The dyeing conditions were composed of combinations of pH (3, 5, 7, 9), temperature (10, 30, 55, $80^{\circ}C$), and time (10, 30, 60 min). The results indicate that palmatine was comparable to berberine in the dyeing behaviors tested for this study and the results were statistically significant. The dye exhaustion and dye uptake of palmatine-CH were slightly lower than berberine-C, which however were not statistically significant. Similar to berberine-C, palmatine-CH favored a pH 7 condition for both dye exhaustion and dye uptake. However, palmatine-CH favors a higher dyeing temperature and longer dyeing time than berberine-C for superior dyeing results.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.369.3-369.3
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• 2002

Albizzia julibrissin Durazz (Leguminosae) is a small domed to flat-topped, spreading tree with smooth. gray-brown bark and doubly pinnate leaves. It grows abundantly in Korea. The dried stem bark of A. julibrissin is used as a tonic in China, Japan and Korea. From the stem bark of A. ju/ibrissin, a new unsaturated hydroxy fatty acid was isolated and characterized as 4-hydroxy-dodec-2E-enedioic acid on the basis of several data including 2D-NMR. (omitted)