The Effects of Resin Tapping on the Radial Growth of Masson Pine Trees in South China-A Case Study
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Research article Agri Res & Tech: Open Access J Volume 8 Issue 2 - July 2017 Copyright © All rights are reserved by Roger Williams DOI: 10.19080/ARTOAJ.2017.08.555732 The Effects of Resin Tapping on the Radial Growth of Masson Pine Trees in South China-A Case Study Roger Williams*, Callie Nauman and Jiawei Zhu School of Environment and Natural Resources, The Ohio State University, USA Submission: June 21, 2017; Published: July 13, 2017 *Corresponding author: Roger Williams, School of Environment and Natural Resources, 210 Kottman Hall, 2021 Coffey Road, The Ohio State University, Columbus, OH 43210, USA, Tel: ; Fax: ; Email: Abstract Five Masson pine (Pinus massoniana Lamb for this study. Two plantations were tapped for resin production and three plantations had not been tapped. Eight sample trees were selected from each of three sample plots randomly established.) plantations in each near plantation. Liuzhou, Tree Guangxi cores werein south extracted China rangingat 1.3m inon age each from sample 14-18 tree years for the were purpose selected of treesmeasuring and 24 tree cores ring from width untapped to establish trees radial were growth.used for Tree analysis. cores The were mean sanded radial with growth fine grain of tapped sandpaper trees (4.4712mm) and measured and to untapped the nearest trees 0.5mm (4.3537) with the aid of a 10x magnification scope. Some cores had to be eliminated from the sample due to poor quality, and ultimately 24 cores from tapped trees.were foundWhile toour be results not significantly would suggest different that there (p=0.05). is no impactModels of were tapping developed trees for to resin display on diameterthe cumulative radial growth,radial growth this might of trees, be misleading. and the 95% We confidence bounds about the model coefficients suggest there is no significant difference in the cumulative radial growth of tapped and untapped 1.3m may actually have been a positive effect. There could have been an increase in the radial growth due to the wood formation in the uninjured sampled only at 1.3m and it is possible that had we sampled at 3.0m we might have recorded a negative effect. The “non-effect” we recorded at sideKeywords: of the tree, Resin but tapping; was not Pinus significantly massoniana; greater Tree than rings; that Radial of untapped growth; trees. Non Implicationswood forest productsof this finding are discussed. Introduction Masson pine (Pinus massoniana Lamb), a native species of growth resources, i.e., carbohydrates, of the tree move toward central and southern China, has long been used as a main source loss and insect and pathogen penetration [7,8]. Accordingly the wound for the purpose of resin production for defense and of pine resin in China. Turpentine and rosin are extracts from healing. Therefore concerns arise whether tapping trees has a the resin which are used to produce a variety of products such negative impact on the tree growth. as solvents, cleaning agents for varnishes and paints, production Studies regarding the impact of resin tapping on tree growth perfumes, synthetic rubber, disinfectants, coatings, printing ink of flavor and fragrances in the pharmaceutical and food industry, increase in tree radial growth of Scots pine (Pinus sylvestris L.) have produced conflicting results. Some studies [9,10] found an for resin extraction, Masson pine also has high value in regard to as a result of tapping based on their measurements of tree ring resins, and waterproofing materials [1-3]. In addition to its value Masson pine trees had a negative impact on radial growth. its use in the wood, pulp and paper industry. In fact, one study width at breast height. However, others [11] found that tapping Pinus demonstrated the potential economic benefits of combined elliottii Engelm.) in south China resulted in reductions in tree resin collection and timber production in the same stand [4]. Likewise another study [12] found that tapping slash pine ( diameters and stocking volume. Sometimes, however, it is more profitable for forest famers to tap treesThe for production resin than harvestingof resin is a [5]. defensive response of the tree to differences in the autecology of a species, sampling design, and It is apparent that there are different factors, such as site to form a physical and chemical barrier to prevent water even the resin extraction method, that could produce these a mechanical wound [6] where the resin flows into the wound Agri Res & Tech: Open Access J 8(2): ARTOAJ.MS.ID.555732 (2017) 0025 Agricultural Research & Technology: Open Access Journal by rolling topography, which are dominated by moderately determine if more light can be shed onto the subject of the effect developed arenaceous shale red soils and strongly developed apparent conflicting results. It was the purpose of this study to of tapping trees for resin on tree growth. The subject species was Masson pine and the extraction method studied was the Chinese clayData arenaceous collection shale red soils [14]. Planted Masson pine stands, two tapped for resin and three Materialsmethod that and utilizes Methods downward-pointing V-shaped grooves. untapped (Table 1), were sampled in May of 2013. The method Study area used for tapping trees for resin was what has been referred to This study was conducted in the forests surrounding the as the Chinese method, where V-shaped grooves are cut daily, near the city of Liuzhou in the Guangxi Province. The forest deep enough to reach the secondary xylem. The first groove Guangxi Eco-Engineering Technical and Vocational College are cut below it. The groove reaches roughly half way around (approximately N24°29’ latitude, E109°22’ longitude) is cut about 1.2m above the ground, and subsequent grooves tree’s circumference and no chemical stimulants are used. occupies 1,215 hectares and is comprised mostly of planted (Cunninghamia lanceolata both tapped and untapped stands were all approximately the (Lamb.) Hook.) and eucalyptus hybrid (Eucalyptus urophylla Plantations were selected based on age (10-20 years) and that stands of Masson pine, Chinese fir same age. Plantations were sampled by randomly establishing x E. grandis). This region lies within the southeastern edge mean annual temperature within the region is 21.1° C, with a three circular 0.05ha plots in each plantation. The diameter-at- of the subtropical monsoon climate areas of China [13]. The 1.0m) were measured and recorded with a diameter tape and breast-height (dbh, nearest 0.1cm) and total tree height (nearest clinometer, respectively, for each tree on the plot. At the plot average annual precipitation ranges from 1200 to 1500 mm with maximum of 40.3° C in the summer and -1.5° C in winter. The center the slope percent and aspect were measured at the plot center using a clinometer and compass, respectively. geomorphic types are lower mountains and hills, characterized Tableaverage 1: Plantationrelative humidity attributes rangingof Masson from pine 80plantations to 84%. used The in main this study located near Liuzhou, Guangxi in south China. Azimuth Basal Area Average Dbh Average Tapping Status Age (Years) Slope (%) Trees Per Ha (Degrees) (M2/Ha) (Cm) Height (M) 14 45 1 1593 33.8 14.4 Untapped 14 195 4 1220 31.9 16.118.1 18 152 31 28.4 14 1613 14 290 1033 17.3 15.8 Tapped 1697 18 203 68 1533 26 15.1 13.7 Statistical analysis28.6 Each plot was divided into quadrants, and two trees were represented the diameter distribution in the plot for tree ring selected from each quadrant (for a total of 8 trees per plot) that differences existed in the annual tree ring width between tapped measurement. One tree core was collected from each of the Analysis of Variance (ANOVA) was used to determine if increment borer at 1.3m up the bole of the tree. On tapped trees, and untapped trees. Duncan’s multiple range test (p=0.05) was eight sample trees on each plot with a 3-thread, 5.15mm bore the core was collected on the side of the tree opposite the tapping used to determine significant differences between the mean tree model was developed to represent the accumulating radial location. The cores were placed into a core holder and labeled ring width between tapped and untapped trees. A non-linear growth for comparison between tapped and untapped trees. A for the purpose of measuring growth rings. Cores were sanded model of the form: The widths of growth rings were measured to the nearest 0.5mm b with a fine-grain sand paper for easier visibility of growth rings. Y = a(x) Because of the poor condition of some cores, it was determined with an engineer’s scale and the aid of a 10x magnification scope. Where Y=cumulative radial diameter growth (mm), x=the that some of these cores would not provide accurate, consistent number of years of growth, and a and b are estimated equation measurements of growth rings and were thus eliminated from coefficients, was used. The model coefficients were estimated the sample pool. Accordingly, this left 38 core samples from using the Non-Linear Procedure, Gauss-Newton method in SAS were met for the models of both tapped and untapped trees. software, version 9.2 [15] and the specified convergence criteria untapped forests and 24 samples from tapped forests. In order Results and Discussion samples were randomly selected and eliminated from the sample to acquire equal sample sizes for comparison purposes, 14 core Analysis of variance and Duncan’s multiple range tests reveal size of 24 cores each for tapped and untapped forests. pool representing untapped forests. This left an equal sample growth (tree ring width) between tapped trees and untapped that there was no significant difference in the mean annual radial How to cite this article: Williams R, Nauman C, Zhu J.