Variability in the Natural Termite Resistance of Plantation Teak Wood and Its Relations with Wood Extractive Content and Color Properties

Property of natural termite resistance of teak (Tectona grandis)wood signifies one of its most important characteristics. With the purpose of understanding the variation in such resistance, four teak trees in the form of trunk (stem) from Randublatung , Central Java were randomly selected, and each wood portion sampled in radial and axial direction. Extractive content and color properties of the teak wood were also measured and correlated with properties of its natural termite resistance. Bioassay test was conducted by no-choice feeding method using Reticulitermes speratus Kolbe termites. The extractive contents were determined by successive extraction using n-hexane, ethyl acetate, and methanol, respectively. Color properties were measured with the CIELAB system. Results showed that antitermitic activity of the teak wood was affected by radial and axial position in the corresponding tree. The wood from middle part of the trees in axial direction exhibited the most resistant to termites (mean mass loss = 1- 4 mg ), while in radial direction the sapwood exhibited the least resistance ( greatest mass loss), and moving inward to the near-pith heartwood the resistance tended to decrease somewhat (slight increase of mass loss). Heartwood and sapwood part differed significantly in ethyl acetate and methanol- soluble extractive contents. Apparently, the greater the ethyl-acetate-soluble extractives (EEC) then the higher the termite resistant (lower mass loss), and conversely the greater the methanol- soluble extractive (MEC) then the lower the termite resistant ( greater mass loss). The brightness index (L*) and redness index (a*) varied significantly in radial direction, however, no significant variation was found in color properties within the heartwood. No strong degree correlation was measured between the mass loss due to termite activity and extractive content parameters. In both heartwood and sapwood, a significant negative correlation (r = -0.50) was found between the mass loss and redness (a*), while correspondingly a significant positive correlation (r = +0.54) occurred between brightness and mass loss. These occurring phenomena strongly suggested that the red colored teak wood was brought about by the moderately polar EEC (e.g. tannin, quinone, and other polyphenol) that inflicted teak-wood resistance against termite (lower mass loss), while the bright-colored teak wood was due to the highly polar MEC (e.g sugar and other soluble carbohydrate) which were conversely responsible for lowering termite resistance ( greater mass loss)

Pengukuran Kadar Ekstraktif dan Sifat Warna pada Kayu Teras Jati Doreng (Tectona grandis)

Measurement of Extractive Content and Color properties on Black-streaked Heartwood of Teak (Tectona grandis)Teak (Tectona grandis L.f) in certain areas of Java usually has black streaked heartwood or has been known as "doreng". In general, the color of wood is related to the kinds and amounts of extractives, therefore, black streak that appeared on the heartwood was studied by means of color measurements and the determination of extractive content. The study was made with 13 trees of black streaked heartwood and 5 trees of normal heartwood. The wood powder (40-60 mesh) was extracted successively with ethanol-benzene (1:2, v/v) for 8 h and hot water for 3 h. The used system of color measurements was CIEL*a*b* which represents brightness, redness and yellowness. The discolored wood was contained substantially more ethanol-benzene soluble extractive content (12 - 22%) than did the normal heartwood (7 - 11%). The yield differences of hot-water soluble extracts were not as pronounced. Beside the brightness (L*), the differences in redness (a*) and yellowness (b*) between the normal (L* = 51-61, a* = 4 to 7, b* = 24 to 28) and black streaked heartwood (L* = 42-51, a* = 6 to 9, b* = 20 to 25) before the extraction, were notable. The total color differences ( E*) before and after extractions, however, were not significantly differed between the discolored ( E* = 6 to 13) and normal heartwood ( E* = 5 to 11) parts. Correlation analysis revealed strong correlations between ethanol-benzene soluble extractive content with L* (r = -0.97) and b* (r = -0.94). The hot-water soluble extract was moderately correlated with a* (r = 0.54) and the difference in redness ( a*) before and after extractions (r = 0.75)

Correlation between Extractive Content and Colour Properties in Teak Heartwood

Beside for its high natural durability and resistancy of  weather properties, teak (Tectona grandis) wood is also valued for its beautiful grain and colour. Theoretically, wood colour is highly affected by extractive content, particularly in the heartwood. Identification of correlation between wood colour and extractive content was determined through wood colour and extractive measurements on the outer part of heartwood zone. The wood samples were collected from two locations of Perum Perhutani forest plantations, i.e. KPH Randublatung (35 trees, age class III-IV) and KPH Purwakarta (32 trees, age class VI). Samples were cut from bottom part of the trees and then ground into powder measuring of 40-60 mesh. The wood colour properties(CIE-L*a*b, CIE-L*C*h, CIE-X*Y*Z, Munsell Colour Chart and ISO Brightness) were then measured. Solubility of  the teak wood extractives were determined by extracting the powder in ethanol-benzene and hot water respectively. Results showed that the range of colour properties were L*= 40-62; a* = 3-11; b* = 19-31; C* = 20-31; h0= 70-82; X= 10-25; Y= 8-23; Z=4-13; H=5-8; V =3-8; C =3-6; and W (ISO Brightness) = 4-12. Different sample location resulted in different trends of correlation between colour properties and extractive contents. No significant correlation was found between extractive solubles in hot water and colour parameters. In general, the best correlations were encountered between brightness parameters from CIE-L*a*b* or ISO with ethanol- benzene extractive contents (r=- 0.54 or 0.50, respectively)

Kilas Balik Sepuluh Tahun Jurnal Ilmu Kehutanan

Kilas Balik Sepuluh Tahun Jurnal Ilmu Kehutana

Suitability of Teak Log Quality from Gunung Kidul and Bantul Yogyakarta Community Forest for Export Meubel Purpose

Natural defect or poor log quality are common in community teak forests. Furniture manufacturers typically use these log types for export purposes. The aim of this study is to determine the effect of community teak forest location and teak stand age affect on teak wood quality. Three teak forest locations were Bantul and two locations in Gunung Kidul. The teak stand age class namely 6, 8, and 10 years old. The data was analyzed using SPSS 20.0 with Tukey test. The result showed that brittleness defect, sapwood defect, and different wooden knot defects were significant in all locations, while log straightness defect was found only in Dlingo. Similarly, all teak stand age (6, 8, and 10 years old) also produced the same defects such as brittleness defect, sapwood defect, and wood knot defect, while the straightness defect at the age of 10 years old was different from to other two teak stand age (6 and 8-year-old). Average teak log defects were straightness defect 1.87-3.53%, brittleness defect 1.19–6.21%, sapwood defect 1.49-4.82 cm, and wood knot defect 5.10-11.46 cm. However, the teak log quality still met the SNI 7534.2-2010 and 7535.2-2010 as raw material for exporting furniture

Studi Mutu Kayu Jati di Hutan Rakyat Gunungkidul. VI. Kadar Zat Anorganik dan Keasaman

Zat anorganik dan keasaman telah terbukti dalam mempengaruhi sifat-sifat kayu. Paper-paper sebelumnya dalam seri ini telah membahas sifat fisik dan kimia kayu jati dari hutan rakyat. Untuk itu, penelitian ini bertujuan untuk mengeksplorasi kadar zat anorganik dan keasaman kayu jati dari hutan rakyat Gunungkidul di 3 tempat tumbuh dengan zona ekologis berbeda (Panggang, Playen, Nglipar). Parameter yang diteliti adalah nilai pH, kadar abu (ASTM D-1102), kadar silika dan silikat (SNI 14-1031-1989), dan kadar unsur zat anorganik (Ca, Mg, K, Na, Fe, Mn, dan Cu) melalui Atomic Absorption Spectrophotometer. Kisaran kadar abu serta kadar silika dan silikat secara berurutan adalah 0,38-2,62%, dan 0,01-1,17%. Kisaran nilai kadar zat anorganik Ca, K, Mg, Na, dan Fe adalah 408–2919 ppm; 69-23705 ppm; 947-1653 ppm; 4-31 ppm; dan 0-326 ppm, secara berturutan sedangkan Mn dan Cu tidak terdeteksi di semua sampel. Selanjutnya, kisaran nilai pH yang diperoleh sebesar 5,23 – 6,98. Berdasarkan analisis variansi, kadar abu, silika-silikat, dan Na dipengaruhi oleh faktor tempat tumbuh dan arah radial pohon (gubal, teras luar, dan teras dalam). Kayu dari Playen (zona tengah/Ledok Wonosari) menunjukkan nilai yang cukup tinggi untuk kadar abu dan silika-silikat. Faktor arah radial pohon berpengaruh nyata pada unsur Ca, K, dan Mg melalui uji Kruskal-Wallis. Dari analisis korelasi Pearson, didapatkan hubungan kuat antara kadar abu dengan kadar silika-silkat (r = 0,77-0,88) serta kadar abu-Ca (r=-0,51) dan kadar abu-Mg (r=0,59) di bagian teras. Dalam tingkat unsur, hubungan terkuat diamati pada kadar Ca-Mg (r = -0,46). Perhatian khusus perlu diberikan pada kadar silika-silkat yang relatif tinggi di sampel yang diamati karena pengaruhnya terhadap penumpulan peralatan gergaji.Study of Teakwood Quality from Community Forests in Gunungkidul. VI. Inorganic Material Contents and AcidityAbstractInorganic materials and acidity in the wood has been proved to affect the wood properties. The previous paper in this series reported on the physical and chemical properties of teak wood from community forests. Therefore, this study aimed to explore the content of inorganic materials and acidity of teak wood grown in the 3 sites (Panggang, Playen, Nglipar) with different ecological attributes from community forests in Gunungkidul. The evaluated parameters were pH values, the contents of ash (ASTM D-1102), silica and silicates (SNI 14-1031-1989), and inorganic matters (Ca, Mg, K, Na, Fe, Mn, and Cu) by means of Atomic Absorption Spectrophotometer. The ranges of ash and silica-silicates content were 0.38-2.62%, and 0.01-1.17%, respectively. The ranges of inorganic element content for Ca, K, Mg, Na, and Fe were 408–2919 ppm; 69 – 23705 ppm; 947–1653 ppm; 4 – 31 ppm; and 0 – 326 ppm, respectively whereas Mn and Cu were not detected in any samples. Further, the obtained pH values range was 5.23–6.98. On the basis of analysis of variance, the contents of ash, silica-silicates, and Na were affected significantly by site and radial direction (sapwood, outer heartwood, and inner heartwood) factors. The woods from Playen (middle zone/Ledok Wonosari) had significantly high in ash and silica-silicate contents. By Kruskal-Wallis test, radial direction factor affected significantly the levels of Ca, K, and Mg. As defined by Pearson’s correlation analysis, it was found a strong correlation between the ash and silica-silicates contents (r=0.77-0.88), as well as between the ash-Ca content (r=-0.51) and the ash-Mg content (r=0.59) in the heartwood part. In the inorganic element levels, the strongest correlation was measured between Ca-Mg content (r=-0.46). Special attention should be given to the comparatively high amounts of the silica-silicates content in the observed samples as it would dull cutting tools considerably

Chemical properties of modified mahogany wood by heat treatment

Mahogany woods from community forests generally have relatively low qualities due to lack of maintenance activities and for their young harvesting stage. Heat treatment is known as wood modification method that could improve the quality of the wood. The aim of this study was to determine the interaction effect of temperature and method of heat treatment on the chemical properties of young mahogany wood. Materials used in this research were mahogany wood boards from community forest which were heat-treated using oven and steam methods performed at the temperature of 90°C, 120°C, and 150oC for 2 hours. In this research, some chemical changes were analyzed. Results of the research showed that the interaction of temperature and heat treatment method gave a significant decreasing on the pentosan amount, and hot-water extractive solubility, particularly the steaming at 150oC. The increasing temperature of heat treatment significantly decreased the content of holocellulose, α-cellulose, hemicellulose, and pH values whereas it increased lignin content,  extractives (cold-water and alcohol-benzene extractives) and solubility in 1% NaOH. Steaming method provided lower levels in the content of holocellulose, ethanol-benzene extract, cold-water solubility, and pH values compared to the oven heating. However, the steaming method over 1200C should be considered as it would reduce the wood strengths

Kadar Ekstraktif dan Sifat Warna Kayu Jati Plus Perhutani Umur 11 Tahun dari KPH Ngawi

Pemanfaatan kayu jati dari pohon umur muda meningkat disebabkan adanya kesenjangan permintaan dengan ketersediaan kayu. Perhutani menanam pohon Jati Plus Perhutani (JPP) dengan karakteristik cepat tumbuh untuk meningkatkan produksi kayu jati. Pembiakan secara vegetatif ini diduga bisa berpengaruh terhadap sifat-sifat kayu. Kadar ekstraktif menjadi penting mengingat hubungannya dengan keawetan alami kayu dan sifat warna kayu. Penelitian ini bertujuan untuk mengetahui variasi kadar ekstraktif dan warna pada arah radial dan longitudinal kayu JPP. Sampel kayu diambil dari tiga pohon JPP berumur 11 tahun di KPH Ngawi. Faktor yang diamati terdiri dari arah longitudinal (pangkal, tengah, ujung); dan radial (gubal, teras terluar, teras terdalam). Kayu diekstrak secara berurutan dengan pelarut toluena, etanol, air panas pada alat soklet. Kadar fenolat total diuji dengan metode Folin-Ciocalteu untuk ekstrak toluena. Pengukuran sifat warna menggunakan sistem CIEL*a*b*. Hasil menunjukkan bagian pangkal memiliki kadar ekstrak terlarut etanol tertinggi, tetapi memiliki kadar fenolat total relatif rendah. Nilai kecerahan (L*) lebih tinggi di bagian ujung dibandingkan dengan bagian tengah dan pangkal sedangkan nilai kemerahan (a*) relatif tinggi di bagian pangkal. Secara nyata, ekstrak terlarut toluena, ekstrak terlarut etanol, dan kadar fenolat total di bagian gubal berbeda nyata dengan bagian teras dan terdapat perbedaan antara teras terluar dan teras terdalam pada kadar esktraktif terlarut toluena dan kadar ekstraktif terlarut etanol. Berdasarkan variasi radial, warna lebih gelap di bagian teras terluar dibandingkan bagian lainnya. Kadar ekstraktif terlarut air panas memiliki hubungan yang nyata (r = -0,72) dengan nilai L* di bagian gubal. Pada bagian teras, nilai L* memiliki hubungan negatif dengan kadar ekstrak terlarut etanol (r = -0,70), kadar ekstraktif terlarut air panas (r = -0,52), dan kadar ekstraktif total (r = -0,78). Secara nyata, nilai a* memiliki hubungan negatif (r = -0,58) dengan kadar fenolat total. Relatif rendahnya kadar ekstraktif dibandingkan umur dewasa serta tidak seragamnya sifat warna pada arah longitudinal perlu menjadi perhatian dalam pemanfaatan kayu JPP umur muda. Extractives Content and Colour Properties of 11-year-old Perhutani Superior Teakwood from Ngawi Forest Management UnitAbstractThe utilization of young teak wood had increased due to the gap in demand and the supply of raw materials. To meet the high demand, Perhutani had planted the fast growing of superior teakwood (Jati Plus Perhutani/JPP). This vegetative reproduction may affect the wood properties. Extractive content is important considering its relationship with the natural durability of wood and colour properties. The purpose of this study was to find out the effect of radial and longitudinal directions on extractives content and colour properties from JPP. The JPP wood samples (11 years) were located in Ngawi Forest Management Unit. The observed factors were vertical (bottom, center, top) and radial (sapwood, outer heartwood, inner heartwood) directions. Wood extracts were obtained by successive extraction (toluene, ethanol, and hot water) in a soxhlet. Total phenolic content was also determined by Folin-Ciocalteu method in toluene soluble extract. Colour properties were determined by CIEL*a*b* system. The result showed that vertical direction had significant effect as the bottom part showed the highest value in ethanol extract content but it had lower value in total phenolic content. Brightness (L*) value was comparatively high at the top part, while redness (a*) value was high at the bottom part. The levels of toluene, ethanol, and total extract content had a significant different between sapwood and heartwood as well as between outer heartwood and inner heartwood. Based on radial direction, the colour was darker in outer heartwood compared to the other parts. The correlation degree between the values of hot water extract and L* was significant (r = -0.72) in sapwood part. In heartwood, the correlation between ethanol, hot water, and total extract contentwith L* values were negative (r = -0.70; -0.52; -0.78, respectively). The correlation between a* value and total phenolic content was moderately significant (r = -0.58). The comparatively low content of extractive compared to mature woods as well as inhomogeneity of colour properties in vertical position should be noticed for young JPP wood utilization

Studi Komponen Kimia Kayu Eucalyptus pellita F. Muell dari Pohon Plus Hasil Uji Keturunan Generasi Kedua di Wonogiri, Jawa Tengah

Eucalyptus pellita F. Muell (E. pellita) merupakan salah satu jenis tanaman cepat tumbuh yang sedang dikembangkan melalui program pemuliaan. Pengembangan jenis ini sudah memberikan hasil yang cukup memuaskan dari sifat pertumbuhan genetika pada uji keturunan generasi pertama dan kedua. Penelitian ini bertujuan untuk mengetahui kandungan kimia kayu, mengelompokkan dan memeringkatkan pohon plus berdasarkan komponen kimia untuk mendukung program pengembangan uji keturunan generasi berikutnya, khususnya kayu untuk pulp dan kertas. Bahan yang digunakan adalah sampel yang berasal dari 61 pohon plus E. pellita umur 9 tahun yang ditanam di uji keturunan generasi kedua Wonogiri dan berasal dari 6 provenan berbeda. Pengambilan sampel dilakukan dengan sistem bor riap pada pangkal pohon setinggi 90 cm dari permukaan tanah. Hasil bor riap digiling hingga diperoleh serbuk kayu dengan ukuran 40-60 mesh. Pengujian sifat kimia kayu mengacu pada standar ASTM. Pengujian tersebut mencakup kadar ekstraktif etanol-toluena dan air panas melalui ekstraksi berurutan, kemudian kadar holoselulosa, alfa-selulosa dan lignin. Analisis data menggunakan analisis deskriptif dan gerombol. Hasil analisis menunjukkan kisaran kadar ekstraktif etanol-toluena dan air panas secara berurutan adalah 1,87 - 10,92 % dan 0,64 - 10,00 %. Kisaran kadar holoselulosa, alfa-selulosa dan lignin adalah 72,89 - 79,91 %, 41,84 - 54,85 % dan 22,12 - 36,61% secara berurutan. Koefisien variasi yang tinggi diamati pada parameter kadar ekstraktif (30,78 - 82,91 %). Berdasarkan hasil pemeringkatan sederhana yang dilakukan melalui analisis deskriptif dan gerombol diperoleh 13 individu pohon plus terbaik sebagai bahan baku pulp.Katakunci: Eucalyptus pellita, kimia kayu, selulosa, analisis gerombol, seleksi pohon A Study on Chemical Composition of Eucalyptus pellita F. Muell Wood from Progeny Test Second Generation Tree in Wonogiri, Central JavaAbstractEucalyptus pellita F. Muell (E. pellita) is one of the fast growing species, which is being developed through tree breeding program. The development of this species had produced good results in the genetic growth characteristics in the first and second generation of progeny trials. The objectives of this research were determining the variation of wood chemical components, clustering and rating the plus trees to support the development program in next generation of the progeny trial, especially in pulp and paper purposes. The materials were the 61 plus trees of E. pellita trees 9-years-old from second generation of progeny trial, Wonogiri in six different provenances. The sampling used the increment borer system at 90 cm from the surface. Materials from the increment borer were milled to 40 - 60 mesh of wood powder. The wood chemical properties were tested according to ASTM standards. It included ethanol-toluene and hot-water solubles by sequential extraction as well as holocellulose, alpha-cellulose and lignin contents. Data analysis used descriptive and clustering analysis. The results showed that the range values of ethanol-toluene extractives and hot water content respectively were 1.87 - 10.92 % and 0.64 - 10.00 %. The range values of holocellulose, alpha-cellulose and lignin contents were 72.89 - 79.91 %, 41.84 - 54.85 % and 22.12 - 36.61 %, respectively. The high values of coefficient of variation were observed in extractive content levels (30,78 - 82,91 %). Based on the simple rating, which was resulted from descriptive and cluster analysis, it gave the best 13 individuals of plus trees for pulp and paper purposes