Mature Teak Research Articles

Measurement of Microfibril Angle Using X-Ray Diffraction and Light Microscope on 5-year-old Super and Conventional Teak Wood

The long harvest time causes the processing industry manufactured from teak wood (Tectona grandis L. f.) has experienced a lot of declines. To overcome this problem, currently, in Indonesia many types of fast-growing teak have been developed, one of which is Jati Unggul Nusantara (JUN). Trees that are accelerated in growth, are likely to cause changes in their anatomical structure. The anatomical structure of wood is one of the basic properties that greatly influences the use of wood as a raw material. Even small changes in cell shape and size can change the properties of wood as a raw material. One of the anatomical structures of wood, namely the ultramicroscopic structure that affects the quality of wood, is the microfibril angle (MFA). The purpose of this study is to determine the MFA of JUN at the planned cutting age of 5 years, compared to conventional teak at the same age. There are two methods used, namely using X-Ray Diffraction (XRD) and measuring the elongation of the pit apertures slope of the fiber cells using a light microscope, which was obtained from the maceration process. As a result, JUN's MFA is 22.09°, smaller than the conventional teak of 25.29°. This is because JUN was developed from top cuttings so although still young, it already reflects the characteristics of mature teak. The results of the MFA measurements on JUN using two methods (XRD and light microscope), resulted different values. It is different from the MFA measurement results on conventional teak. It is recommended to measure the MFA in JUN wood by using XRD, because possibly, due to accelerated growth, simple pits with an oval shape turn into circular. This difference causes the results of the JUN MFA measurement using a light microscope based on the pit apertures slope to be inconsistent, subjective, and different results in other pits contained in the fiber even though they are closely associated. However, in conventional teak, measurements using a light microscope are possible because the shape of the pit is oval so that the slope of the elongation of the pit aperture can be determined easily, and is more consistent with more uniform values in the same individual fiber

Utilisation of Tectona grandis (teak) leaf extracts as natural hair dyes

AbstractThere is now a preference for hair dye products containing natural dyes because they are safer for human use. Teak leaves contain flavonoids, anthraquinones and naphthoquinones, and their extracts can be used as natural dyes. The objective of this research was to evaluate the use of teak leaf extracts as natural hair dyes. This research was carried out on both young and mature teak leaves that were extracted either with water or with ethanol‐water mixtures using the decoction method. The colour substances in the extracts were studied by quantifying the flavonoid and anthraquinone content, and identified using liquid chromatography‐mass spectrometry (LC‐MS); the colour values were measured with the CIELab system. The solubility, stability and hair dyeing efficacy of the extracts were assessed. The results showed that young leaf extract is redder with a higher total flavonoid content than mature leaf extract. Fifty percent ethanol was the best solvent for extracting the high flavonoids from teak leaves. Polysorbate 20 significantly increased the water solubility of both young and mature leaf extracts. Hair dyed with young leaf extract became reddish brown, while hair dyed with mature leaf extract became brown. Stability testing found some flavonoid degradation of the extracts, but only slight colour changes occurred in the extracts. The LC‐MS profiles showed high‐intensity flavonoid peaks that could be applied to control the colour quality of the extracts with other parameters. These results demonstrate that teak leaf extracts are effective natural hair dyes that can be used in the development of hair dye products.

Physical and Chemical Characteristics of Teak (Tectona Grandis) Leaves as Food Packaging Material

Teak (Tectona grandis) leaves is commonly used as the packaging material of traditional food in Indonesia. This study aimed to determine the physical and chemical characteristics of teak leaves with various maturation stages to obtain information about the potency of teak leaves as active packaging material. The physical characteristics analysis including leaf color, thickness, and tensile strength, while chemical characteristics were moisture, fat content, fatty acid, and volatile profile. The results showed that the color, thickness, tensile strength, moisture, and fat content, were light green, 0.306±0.024 mm, 0.22±0.114 MPa, 74.93%, and 2.52% respectively for young teak leaves; while the mature has darker green, 0.388±0.001 mm, 0.36±0.163 MPa, 73.05%, and 2.54% respectively. The fatty acid profiles showed that young teak leaves contained 5 types of fatty acids, dominated by lignoceric acid; while mature teak leaves contained 9 types of fatty acids dominated by tricosanoic acid. The volatile components of young teak leaves e.g. acid and ester compounds, while the mature was dominated by acid and ether compounds. From the results, it is suggested that the use of teak leaves as active food packaging material can be scientifically justified.

Biomass carbon stock and water yield of teak catchments

Rehabilitation of degraded forests and lands using the vegetative method can be used to improve the environmental condition and sequestered carbon dioxide from the atmosphere. However, improper plant selection may create water shortage in dry season. Based on the background, the research was conducted in order to study the relationships of biomass carbon stock, evapotranspiration, and water yield of five catchments covered by various teak areas. The study was conducted in Blora Regency, Central Java, Indonesia. The percentage of mature teak plantation areas in the catchments were 82, 82, 73, 70, and 53%. The biomass carbon stock in each catchment was estimated using previously published data. The water yield of the catchments was calculated from the conversion of the stream water level at the outlet of each catchment. The evapotranspiration was calculated based on a simple water budget of a catchment. The results showed that the highest carbon stock was 64 t/ha and found in Modang Catchment (82% mature teak). The lowest carbon stock was 22 t/ha and measured in Gagakan Catchment (53% mature teak). In parallel with the amount of carbon stock, the highest evapotranspiration was measured in Modang Catchment, and the lowest was found in Gagakan Catchment. The observation of water yield during 2008- 2019 showed that the higher the carbon stock in the catchments, the lower the water yield. Synergy in reducing CO 2 emission and sustaining water flows can be achieved by considering land suitability for plant growth and applying water conservation in forests and lands rehabilitation.

Wood Properties of 5-year-old Fast Grown Teak

Jati Unggul Nusantara (JUN) is one of fast growing plantation teak that has been widely cultivated in Indonesia. This teak has been developed to be harvested after 5 years when its diameter reaches 25-32 cm (diameter at breast high). The diameter of JUN is usually three times larger than the conventional plantation teak (teak cultivated from seed) at the same age, and the same as 30-40 year-old mature teak. Preliminary research was conducted to determine anatomical and selected physical properties of 5-year-old JUN teak, as well as its suitability for furniture production. The results revealed that wood color, texture, and grain pattern of JUN were slightly different from the mature conventional teak. The length of fiber cells was similar as in the mature teak. There were differences in ultramicroscopic structure of JUN: the mean micro fibril angle was narrower, and the crystallites degree was larger. Shrinkage values from green to 12% moisture content were: 0.70 (radial-R) and 1.62 (tangential-T), and from green to oven dry were 1.59 (R) and 3.29 (T). T/R ratio was 2.34. Specific gravity in air dry condition was 0.52. Based on the research results it appears that 5-year-old JUN may be suitable for the production of medium quality furniture products. More research is required to investigate and enhance the properties of JUN for high quality products.

From shifting cultivation to teak plantation: effect on overland flow and sediment yield in a montane tropical catchment

Soil erosion supplies large quantities of sediments to rivers of Southeastern Asia. It reduces soil fertility of agro-ecosystems located on hillslopes, and it degrades, downstream, water resource quality and leads to the siltation of reservoirs. An increase in the surface area covered with commercial perennial monocultures such as teak plantations is currently observed at the expanse of traditional slash-and-burn cultivation systems in steep montane environments of these regions. The impacts of land-use change on the hydrological response and sediment yields have been investigated in a representative catchment of Laos monitored for 13 years. After the gradual conversion of rice-based shifting cultivation to teak plantation-based systems, overland flow contribution to stream flow increased from 16 to 31% and sediment yield raised from 98 to 609 Mg km−2. This result is explained by the higher kinetic energy of raindrops falling from the canopy, the virtual absence of understorey vegetation cover to dissipate drop energy and the formation of an impermeable surface crust accelerating the formation and concentration of overland flow. The 25-to-50% lower 137Cs activities measured in soils collected under mature teak plantations compared to soils under other land uses illustrate the severity of soil erosion processes occurring in teak plantations.

Soil erosion under teak (Tectona grandis L.f.) plantations: General patterns, assumptions and controversies

High rates of soil loss are usually assumed under teak (Tectona grandis L.f.) plantations and some debate has been created about this during recent years. We analyzed the processes of soil loss and accumulation in a case study and performed a critical review of literature from other studies, due to the shortage of field experimental data from around the world to sustain this theory. The case study was established in Alfisols and slopes ranging from 30 to 60% in Guanacaste, Costa Rica, and compares secondary forests with mature teak plantations and young teak plantations under different management regimes. Over a period of 14months with higher rainfall than the regional average, very little soil loss was registered in the teak plantations of Guanacaste, although there were slight differences between treatments (1–4mm), while soil accumulation was measured in secondary forests (4mm). A number of other authors also report low levels of soil loss in teak plantations and those studies in which high erosion rates have been identified tend to be associated with teak plantations where fires are a common phenomenon. Hence, we conclude that poor forest management (prescribed fires, machinery, extremely steep slopes, previous land use, etc.) rather than the nature of the teak itself causes the high rates of erosion.

First report of a wilt disease of Tectona grandis caused by Thielaviopsis basicola in Brazil

Tectona grandis (teak) was successfully introduced in the Midwestern region of Brazil in the early 1970s and nowadays is an important commercial timber crop in the country. Mature teak trees with wilt symptoms were observed during field…

Biodiversity values of abandoned teak, Tectona grandis plantations in southern Western Ghats: Is there a need for management intervention?

Abandoned plantations could potentially support a large number of native tree species through succession and restore the original tree community. In order to assess the ability of abandoned teak plantations to recover through regeneration, teak stands from 29 to 80 years old were sampled for seedling and sapling density, species richness and the use by large ungulates in the southern Western Ghats using 10m circular plots. The influence of the forest-plantation edge was also studied. There was regeneration of a species-rich tree community in the understorey of abandoned teak plantations. However, regeneration was arrested, and thereby the large girth-class tree community remained species-poor. There was no significant change in the tree species richness with distance from natural forest, suggesting that the forest-plantation edge had little influence on the penetration of native tree species inside plantations. Asian elephant and Indian gaur dung densities were significantly lower in the plantations than in the forest. Indian gaur and sambar used the younger plantations intensively, and the density of their dung was negatively correlated with age of the plantation. Abandonment of mature teak stands arrested the succession of native trees. We provide evidence that abandoned teak plantations might not serve as suitable habitats for large herbivores during the dry months of the year in the region. The study highlights the need for active management of mature teak plantations inside wildlife reserves, in order to promote succession and improve the habitat for wild flora and fauna in the Western Ghats.

Participatory modelling to improve partnership schemes for future Community-Based Forest Management in Sumbawa District, Indonesia

As part of its Community-Based Forest Management (CBFM) Programme, the local government of Sumbawa District in West Nusa Tenggara Province of Eastern Indonesia initiated a partnership programme between the Forestry District Agency and tree grower cooperatives in 2002. The partnership scheme aims to reduce illegal logging and forest encroachment on abandoned state plantations initially developed in 1986. However, the cooperatives have no secure full rights to harvest the mature teak trees ( Tectona grandis) inside the plantations, as important incentives to maintain their commitment. This paper aims to explore the potential benefits of different scenarios, as the basis for convincing the Ministry of Forestry (MoF) to give full secure rights to the local communities. In this study, we used a participatory modelling approach, to identify problems and to define future scenarios of partnership arrangements with the local key stakeholders. This research used the concept of system dynamics modelling, which included the two concepts of systems thinking and resilience. As a management tool, the visualisation of the management alternatives and their associated impacts had stimulated the community's awareness of the importance of protecting the teak plantations from illegal logging and forest encroachment. The simulation results have also shown how granting local communities a full secure access to manage the state forest does not necessarily reduce the revenue for the government at all levels.

Endophytic fungi of teak leaves Tectona grandis L. and rain tree leaves Samanea saman Merr.

In order to study the foliar endophytes from teak (Tectona grandis L.) and rain tree (Samanea saman Merr.) growing in the campus of Chulalongkorn University, healthy leaves were collected at two-monthly intervals during January to December. The number of genera and species, together with their colonization frequency (CF%) in mature teak and rain tree leaves were greater than those in the young leaves. More endophytic isolates in the leaves of both trees were recovered during the rainy season. The fungal genera found in both young and mature teak leaves were Alternaria, Colletotrichum, Nigrospora, Phomopsis and mycelia sterilia. Phomopsis was the dominant genus in both young (newly emerged) and mature leaves. Fusarium, Penicillium, Schizophyllum commune and members of the Xylariaceae were found only in mature leaves. For the rain tree leaves, species of Phomopsis and mycelia sterilia were found in both young newly emerged and mature leaves. Colletotrichum and Penicillium were found only in mature leaves, whereas Nigrospora was found only in young newly emerged leaves. In this study, Phomopsis was the dominant genus in the leaves of both tree species. A total of 37 isolates of endophytic fungi isolated from teak and rain tree leaves were tested for the production of antimicrobial activities. Out of these, 18 isolates could produce inhibitory substances effective against Bacillus subtilis, Staphylococcus aureus and Escherichia coli and 3 isolates inhibited growth of Candida albicans in vitro.

The impact of forest fires on the long-term sustainability of taungya teak reforestation in Bago Yoma, Myanmar

Taungya teak reforestation in Myanmar has a long history and is considered an exceptionally successful example of tropical plantations. However, after one cycle of taungya teak reforestation, soil quality would deteriorate as large volumes of biomass are removed from the forest ecosystem through the harvesting of teak. Therefore, the recovery of soil productivity during the period of teak growth is crucial to the successive rotation of the system. In this study, the dynamics of soil organic matter (SOM) and litter were investigated during the teak growth period to evaluate the long-term sustainability of taungya teak reforestation from the viewpoint of SOM conservation. Especially, the effect of forest fires on SOM dynamics and litter was investigated. In Kabaung Reserved Forest and Bondaung Reserved Forest, where teak reforestation has been practiced since 1884, surface soil samples were collected from teak plantations of different ages (0-96 years) for total carbon and nitrogen content analyses. In mature teak plantations, litter production and decomposition rates of leaf litter were also measured. Accretion of SOM was not observed in any of the teak plantations, even 96 years after reforestation. This absence of SOM accretion was attributed to the combustion of forest floor litter - a main source of SOM - by forest fires. Given that the occurrence of forest fires overlapped the defoliation period of teak, most of the teak litter that had accumulated on the forest floor was easily burnt. The strong positive correlation between total carbon content and the C/N ratio of surface soil in teak plantations suggested that the effect of forest fires on the long-term dynamics of soil carbon was marked. We conclude that forest fires have a detrimental effect on the long-term sustainability of taungya teak reforestation.

Heartwood, sapwood and bark content, and wood dry density of young and mature teak (Tectona grandis) trees grown in Costa Rica

The aim of this study was to evaluate the heartwood, sapwood and bark content, and wood dry density in young and mature teak (Tectona grandis) trees. For this, 17 plantations were selected from 11 sites representing different climatic conditions and plantation densities (156 to 1600 trees ha–1, and line planting). From these plantations, a total of 87 trees with ages between 5 and 47 years were felled for stem analysis. The highest heartwood proportion of stem volume (over bark) was 61% and the lowest 0.4%. The sapwood proportion ranged between 24 and 72%, while bark represented from 14 to 37% of the total volume. Heartwood proportion was significantly different (P < 0.05) among climatic zones: ‘wet’ sites producing less heartwood than ‘dry’ sites. Stem diameter (under bark) and heartwood diameter at different stem heights differed among sample trees, even when plotted in relative values to avoid dependency with stem size. Dry density was statistically different between 8-year-old trees or younger and 47-year-old trees, and between line planting trees and 13-year-old trees or younger, but did not differ statistically between line planting trees and mature trees. No significant differences were found between climatic zones or between different stand densities. Dry density values for T. grandis plantations in Costa Rica are similar to those reported elsewhere.