Chemical characterisation of six wood species from Côte d’Ivoire: macromolecular composition, extractives yields and profiling by GC-MS and FTIR

Aim: Hydraulic conductivity following the Hagen-Poiseuille Law is a quantitative approach to determine the treatability of wood by chemicals. The hydraulic conductivities of the ten selected Nigerian hardwood timber species to four wood treatment chemicals were estimated, using Hagen-Peiseuille equation.
 Materials and Methods: Ten timber species of marketable size and age were sourced from the forestry Departments of Enugu, Anambra and Abia States of Nigeria. Maceration were carried out following standard procedures. The viscosities in centipoises (cp) of the four wood treatment chemicals were measured in a viscometer test, while the hydraulic conductivities were calculated using the Hagen-Peiseuille equation.
 Results: The results obtained show that the different woods responded differently to the chemicals. Treatment with Folithion 200 showed higher conductivity in Triplochiton scleroxylon (9.01 mm-3S-1× 10-5), followed by Mansonia altissima, Milicia excelsa and Terminalia superb. The order of conductivity to treatment with Actellic 25EO was Terminalia superba > Mansonia altissima > Gmelina arborea, > Khaya ivorensis. Ceiba pentandra gave the highest conductivity of 8.58 mm-3S-1× 10-5, followed by Afzelia africana and Canarium schwenfurthii to the chemical Termitox. While Triplochiton scleroxylon gave the highest conductivity of 6.52 mm-3S-1×10-5, followed by Milicia excels and Terminalia superba to the chemical Solignum.
 Conclusion: Folithion 200 would be effective on Milicia excels, Mansonia altissima and Gmelina arborea, Actellic 25 EO would be effective on Khaya ivorensis, Terminalia superb and Antiaris toxicaria while Termitox would be effective on Ceiba pentandra, Afzelia Africana and Canarium schweinfurthii.

Inadequate marketing information about timber species, their sources, market structure and performance has greatly hampered the effectiveness of the business and has hindered investment in the forestry sector. The dearth of market information on market performance and activities have hindered investments in to forest industry and limited its capacity to contribute to economic growth and development of the country. This study therefore analysed timber marketing in Lokoja Metropolis, Kogi State, Nigeria. A semi-structured questionnaire was administered to collect relevant information. Purposive and systematic sampling were applied to determine the study sample which was drawn from three timber markets; Ganaja, Felele and Zango daji. Applying 30% sampling intensity except in markets where the traders were less than ten, 40 timber traders were systematically sampled and interviewed on timber marketing activities. The study identified seven (7) most marketed timber species namely: Daniellia oliveri, Gmelina arborea, Milicia excelsa, Ficus exasperata, Prosopis africana, Triplochiton scleroxylon and Khaya grandifoliola. The major source of timber was from the open forest (92.5%), while supply within the state (27.5%) accounted as the highest, followed by Abuja (20%). The Gini-correlation co-efficient analysis for the study was 0.1552, and this implies that the timber market is imperfectly competitive with the market structure tending towards monopoly. Timber income analysis per truck of the seven species revealed that Daniellia oliveri recorded the highest mean return of 517, 005.99 per month while Ficus exasperata had the least mean monthly gross margin of 35,336.56. The mean gross margin of Khaya grandifoliola, Milicia excels, Prosopis africana, Gmelina arborea and Triplochiton scleroxylon had the same mean returns of 466,270 per month. Low patronage, scarcity of demanded wood species, lack of supply of wood species and high tax were identified as the major challenges facing timber market in the study area. Provision of adequate market education, proper examination and checking of excess associations will improve market efficiency and performance. Therefore, investment into forest development should be encouraged to ensure sustainable supply of raw materials for an efficient market system.

In a completely randomized design, the vegetative growth and nutritive value of three tree leaves Tectona grandis, Gmelina arborea, and Acacia mangium compared to berseem (Trifolium alexandrinum) hay as a standard high-quality roughage for ruminants were studied. Growth, chemical composition, in vitro gas production (GP), and fermentation characteristics for 48 h of incubation were measured. Results of measured growth parameters showed that the highest mean value of total height, stem base diameter, crown width, shoot fresh weight, and shoot dry weight were observed in Gmelina arborea, Tectona grandis, and Acacia mangium, respectively. Gmelina arborea had higher (P < 0.05) concentrations (%) crude protein (CP) and lower acid detergent fiber (ADF) compared to berseem hay. The lowest (P < 0.05) CP was observed with Tectona grandis; however, it had more (P < 0.01) neutral detergent fiber (NDF) compared to the berseem hay. All tree leaves had higher (P < 0.05) concentrations (%) of total phenolics, and total tannins compared to the berseem hay. Furthermore, Acacia mangium had the lowest GP (P < 0.01) GP (mL/g DM) and the rate (h) of GP (P < 0.01), while had the highest (P < 0.05) lag of GP (h) compared to berseem hay. Acacia mangium showed the lowest methane production (mL/g DM) and the highest methane production expressed as mL/g degraded DM (dDM), with no significant differences between Gmelina arborea, Tectona grandis, and berseem hay. At the same time, Tectona grandis showed the highest (P < 0.05) total (mM) and individual (%) short chain fatty acids concentrations compared to berseem hay. Acacia mangium showed the lowest (P < 0.01) truly degraded DM and organic matter (mg/g incubated) and protozoal count (P < 0.05) (105/mL). Also, Acacia mangium had lower (P < 0.05) ammonia-N concentration (mg/dL), metabolizable energy (MJ/kg DM), and microbial protein production (mg/g DM). Overall, Tectona grandis and Gmelina arborea are more recommended than Acacia mangium due to their higher rumen fermentation characteristics and nutrient degradability; however, Acacia mangium has an importance from an environmental view as it had lower methane production compared to other plants.

Logging encompasses all activities involved in the processing of fully developed tree for production of finished and intermediate planks of varying sizes. Energy is a major input for logging. In this study energy audit and analysis was used to determine the specific energy and cost of production. Primary data for the study included site visits and use of questionnaire to collect data on the wood species, energy use pattern and types of equipment used for logging. Measuring instruments such as wattmeter, stop watch and measuring tape were used to measure the current, voltage and power factor; time of operation and size of timber log used in sawmilling in the selected study areaThe study covered 24 sawmills spread across 5 states in the south-western part of Nigeria. The study showed that there are seven wood species in the study area. The specific energy (kWh/m3) and average processing costs per unit volume ($/m3) of the seven species measured in the study area are respectively as follows - Afara (Terminalia superba): 1.65 and 0.094; Iroko (Milicia excelsa): 4.48 and 0.260; Mahogany (Khaya ivorensis): 1.47 and 0.084; Opepe (Naulea diderrichii): 1.77 and 0.100; Omo (Cordia millenii): 0.75 and 0.043; Obeche (Triplochyton scleroxylon): 0.58 and 0.033; Igba (Parkia biglobosa): 1.01 and 0.058.The study showed that the Iroko was the most common wood species processed in the study area and has the highest specific energy for processing. The Iroko was also the most expensive wood specie for log processing in the study area.

The utilization trend of four commonly used wood species and two lesser used wood species that are used for furniture making was examined. The wood species are Mansonia altissima (Mansonia), Khaya ivorensis (Khaya), Cordia millenii (Cordia) and Tectona grandis (Teak) as commonly used wood species; Aningeria robusta (Aningeria) and Gmelina arborea (Gmelina) as lesser used wood species. 154 small-scale furniture factories (SSFF), 28 medium-scale furniture factories (MSFF) and 11 large-scale furniture factories (LSFF) selected through stratified random sampling procedure in Lagos, Ibadan and Benin cities were considered for the study. The quantity (cubic meter) of the six wood species used in making interior furniture such as chair, table, bed cabinet, shelf, wardrobe cupboard and settee from 2001 to 2006 was obtained through a structured questionnaire. The study revealed that in SSFF, the utilization of Khaya, Cordia, Aningeria and Gmelina had been on the increase from year 2001 to 2006 while the trend for Mansonia and Teak did not follow a definite pattern. For MSFF, the trend showed that utilization of Khaya and Cordia increased from 2001 to 2004 and thereafter declined while that of Mansonia and Teak did not follow a definite trend for the 6 years considered for the study. However, Aningeria and Gmelina increased yearly from 2001 to 2006. For LSFF, no definite trend was observed in the utilization of Mansonia, Khaya, Cordia and Teak while Aningeria and Gmelina also increased yearly for the 6 years. The trend for the total wood utilization by the SSFF, MSFF and LSFF showed that Khaya was mostly used by the three scales of furniture industry, followed by Cordia while the utilization of Teak by the three scales of furniture industry was low for the six years of study. There is urgent need for a massive plantation establishment of Teak and Gmelina.

Aim of study: In this study, natural durability of some domestic and foreign wood species against Hylotrupes bajulus and Anobium punctatum larvae were tested on laboratory scaleArea of study: This study was conducted at Department of Forest Products Engineering in Duzce University, Turkey and Federal Institute for Materials Research and Testing (BAM), Germany.Material and Methods: Scotch pine (Pinus sylvestris), fir (Abies nordmanniana), spruce (Picea orientalis), cedar (Cedrus libani), poplar (Populus tremula) and beech (Fagus orientalis) woods were used to test H. bajulus larvae (EN 46-1). Alder (Alnus glutinosa), oak (Quercus cerris), poplar (Populus tremula), beech (Fagus orientalis), maple (Acer carpinifolium), ash (Fraxinus angustifolia), teak (Tectona grandis), ayous (Triplochiton scleroxylon), movingui (Distemonanthus benthamianus), dahoma (Piptadeniastrum africanum), iroko (Chlorophora excelsa), bubinga (Guibourtia tessmannii) and sapele (Entandrophragma cylindiricum) woods were used for A. punctatum larvae (EN 49-1). At the end of the experiment, the mortality rates of the larvae were determined and the size and weights of the surviving larvae were measured.Main results: F. orientalis and C. libani were found to be the most resistant wood species against H. bajulus larvae while A. nordmanniana was the least resistant. All tropical wood species and oak and maple from domestic wood species showed 100% mortality rate therefore found to be the most resistant against A. punctatum larvae. The most vulnerable wood species was found to be alder with a 35% mortality. Research highlights: while F. orientalis, C. libani, and P. tremula were found the most resistance wood species against H. bajulus, P. sylvestris and A. nordmanniana were determined as most vulnerable. All tropical wood species and two domestic species (Q. cerris and A. carpinifolium) showed the highest mortality rate as 100%. The least durable domestic wood was determined as alder.

This study investigated the dimensional stability and strength properties of plastic bonded composites produced from wood waste particles and polyethylene using extruder. The composites were produced from wood species such as such as: Triplochiton scleroxylon, Terminalia superba and Gmelina arborea at a mixing proportion of 60:40 (plastic/wood) on a weight by weight basis. Evaluation of properties was carried out in accordance with the American Standard Testing Methods of 570 and 790 to determine the dimensional stability and strength properties of the composites. The results of findings revealed that water absorption and thickness swelling of the wood composites ranged from 10.08% to 15.36% and 4.33% to 5.58% respectively after 24hours and 48hours immersion in water. Tensile strength also ranged between 29.4MPa and 45.6MPa. Composite board made from T. superba wood particles had the lowest significant water absorption (10.08%), thickness swelling (4.33%) and highest significant tensile strength (45.6MPa) compared to composites produced from G. arborea and T. scleroxylon wood particles. It was observed that high density wood species exhibit lower water intake, lower thickness swelling and higher tensile strength, while the contrary is the case for lower density wood species. In conclusion, the three tree species used for the study could be recommended for the production of wood composite like particle board, fibre board, wood cement boards and others.

The use of biochar has been shown to suppress populations of soil-borne pathogens. Hence it has been promoted as one of the eco-friendly alternatives to synthetic pesticides. In the current study, the effects of different sources of indigenous biochar on Meloidogyne incognita and overall growth and yield of tomato were evaluated under screenhouse condition in 2016 and 2017. A total of 10 treatments were evaluated in the study including tomato plants infected with 5000 infective juveniles of M. incognita treated with biochar woodchips of gum arabic (Acacia nilotica), bush mango (Irvingia gabonensis), neem (Azadirachta indica), goat head (Acanthospermun hispidum), gmelina (Gmelina arborea), locust bean (Parkia biglobosa), lagos mahogany (Khaya ivorensis), fig (Ficus sur), eucalyptus (Eucalyptus camaldulensis) and an untreated control. Treatments were laid-out in completely randomized design (CRD) and replicated four times. Data collected on nematode damage indices, plant height, number of leaves, and fruit yield/plant were subjected to analysis of variance. Means were separated using Duncan’s new multiple range test at 5% level of probability. Among all the biochar treatments evaluated, bush mango (BM) and neem (N) biochars significantly (p≤0.05) reduced root galling index (RGI), infective juveniles and final populations of M. incognita. In 2016 and 2017, the use of BM and N resulted in 64.05 and 66.52% reduction in galling, respectively while neem biochar reduced RGI by 66.49 and 70.76%, respectively and increased yield of tomato by 57.5%. Findings from this study have provided evidence that biochar formulated from indigenous woodchips in Nigeria, especially bush mango (Irvingia gabonensis) and neem (A. indica) are a promising tool in the control of M. incognita. Key words: Biochar, tomato, Meloidogyne incognita, indigenous tree, Nigeria.

Introducción. Los sistemas de producción tradicionales de ganadería generan degradación de suelos, por lo cual es importante implementar sistemas silvopastoriles como una alternativa para la producción bovina de carne y leche. Objetivo. Cuantificar la producción de hojarasca foliar de especies leñosas perennes (Gmelina arborea - Melina, Tabebuia rosea - Roble, Acacia mangium – Acacia) y el aporte potencial de nutrientes al suelo (ciclaje de nutrientes) dentro de sistemas silvopastoriles. Materiales y métodos. Se evaluó la producción y descomposición de hojarasca de especies forestales en campos sembrados con una variedad de gramínea del género Brachiaria, en el Valle medio del Sinú, Colombia, durante mayo a septiembre de 2013. Se utilizó un diseño en bloques completos al azar con tres repeticiones. Los tratamientos utilizados fueron Pr= Brachiaria híbrido cv. Mulato II, SSP1 = Tabebuia rosea + Brachiaria cv. Mulato II, SSP2= Acacia mangium + Brachiaria cv. Mulato II y SSP3= Gmelina arborea + Brachiaria cv Mulato II. Resultados. Hubo mayor producción de hojarasca en especies forestales dentro de los sistemas silvopastoriles. La especie forestal G. arborea obtuvo los mayores aportes potenciales de nutrientes en la hojarasca con el siguiente patrón descendente en kg ha-1: C 4069,6 &gt; Ca 96,47 &gt;N 62,46 &gt; K 37,48 &gt; Mg 23,60 &gt; P 14,57. La hojarasca de la pastura Mulato II y la especie forestal G. arborea exhibieron mayor velocidad de descomposición (k= 1,87 y k=1,77, respectivamente) que el resto de las especies evaluadas. Conclusiones. Las especies forestales evaluadas mejoraron la calidad del suelo mediante un mayor aporte de hojarasca y un mayor aporte potencial de nutrientes.

This study was intended at developing cheap and eco-friendly wood preservatives from Jatropha curcas, Thevetia peruviana and Moringa oleifera seed extracts for the control of termites on Gmelina arborea and Daniellia oliveri wood species. Seeds were collected from Makurdi Timber Shed, dried, and pounded into powder. Seed extracts were prepared using n hexane and hot water extraction methods. The oil extracts were vaporized and 10%, 20% and 30% were constituted. Wooden samples of Gmelina arborea and Daniellia oliveri were cut to 2 cm x 2 cm x 4 cm, air dried for 3 days and soaked in each plant extracts for 24 hours. Randomized Complete Block Design (RCBD) with three replicates was used with a total of 21 treatments including untreated, solvent treated and Solignum treated wood. Phytochemical screening of seed extracts showed the presence of flavonoids and steroids. Incidence of termites attack on Daniellia oliveri wood started from week 3 on 10% Jatropha curcas, Thevetia peruviana, Moringa oleifera oil treated, n hexane treated and untreated. While attack on Gmelina arborea wood started in week 5 on n hexane treated and untreated. Whereas attack on 30% Jatropha curcas, Thevetia peruviana, Moringa oleifera oil treated wood started in week 7. Percentage weight loss of Gmelina arborea wood (17.44%) and Daniellia oliveri wood (25.85%) were least with 30% Thevetia peruviana n hexane treatment compared with unteated Gmelina arborea and Daniellia oliveri wood (58.06% and 69.36%) respectively. It was observed that Gmelina arborea was more resistant to termite attack than Daniellia oliveri.

Surface chemistry and thermo-mechanical analysis of some Nigerian wood species

The study investigated the suitability of selected wood species in the production of turned glue-laminated products. Five different wood species of high quality grades which were sourced from Bodija market Ibadan, south western Nigeria were thoroughly examined where the moisture content, density and shrinkage properties were determined. Among the five different species of wood examined, it was discovered that the highest moisture content (M.C.) (13.4%) was found in Mansonia altisima while thelowest moisture content was found in Nesorgodonia Papaverifera (12%) and this contributes to ease of pest, insect, disease attack and its suitability for the production of turned glue-laminated products. Thespecific gravity or density of wood shows how strong and suitable the wood species are for the production of turned glue-laminated products. Nesorgodonia papaverifera was found to have the highest specific gravity (0.623g) followed by Nauclea diderichii(0.6136g), Gmelina&#160; arborea(0.5565g),Khaya Senegalensis (0.4847g) while Mansonia altisima had the least (0.48g). Shrinkage occurs least in Nesorrdonia papaverifera (5.9%) Nauclea diderichii (7.6%), Gmelina arborea (11.8%), Khaya senegalensis (15%) and occurs most in Mansonia altisima (18.6%). From the study it was shown that the suitability of the wood species for turning were based on strength property, specific gravity or density, shrinkage property and moisture content.The suitability of wood species for turned glue-laminated product is ranked from Nesogordonia papaverifera, Nauclea diderichii, Gmelina arborea, khaya senegalensis to Mansomia altisima.It is therefore recommended that mass production of glue-laminated products be encouraged as the demand is increasing everyday and more of the glue lamination researches be carried out and tested using some lesser used tree species.

The influences of additive concentration and wood species on dimensional stability of cement-bonded flakeboards were investigated. Laboratory scale flakeboards 6mm thick was made from Gmelina arborea (G), Leucaena leucocephala (L) and the mixture of the two in equal proportions. Boards were manufactured at the three levels of the raw materials and additive concentration at levels of 1.5% and 3.5% of the cement weight board. The average values obtained for Thickness Swelling (TS) following 24-hour immersion in cold water ranged from 0.90% to 2.75% for Gmelina arborea; 0.12% to 2.24% for Leucaena leucocephala; 0.39% to 1.68% for mixed materials of the wood species. For 48 hours soak, the values obtained ranged from 1.13% to 3.70%, 1.58% to 3.74% and 0.82% to 2.40% respectively. The values for Water Absorption (WA) after 24-hour water immersion ranged from 15.02% to 17.70% for Gmelina arborea; 15.71% to 19.08% for Leucaena leucocephala; 15.36% to 18.65% for mixed materials. The WA values obtained after 48 hours water immersion ranged from 17.82% to 20.01% for G; 18.77% to 20.93% for L; 18.27% to 20.36% for G + L. The dimensional stability of boards was affected by the wood species, wood density and additive concentration. Boards from Gmelina arborea, were more stable dimensionally than that made from Leucaena leucocephala, whereas the boards produced from the mixture performed better than that of Leucaena leucocephala. The TS and WA of boards decreased with increase the additive concentration. The most dimensionally stable boards were produced at the highest level of additive concentration of 3.5%, both at 24 hours and 48 hours water immersion. TS and WA were not significantly affected by species and species/additive concentration interaction, but the effect of additive concentration was significant.

In southern Aragua state, Venezuela—an area regarded as high priority for local and national development—important sources of income and traditions are related to a history of manufacturing wood products including furniture and woodcraft made of the native tree species Samanea saman. However, scarcity of wood has recently become a major constraint for people of Magdaleno, putting at risk traditional knowledge and employment opportunities. Based on an integrated approach taking into account biophysical, ecological, social and technological issues, a broad group of potential tree species were assessed in a landscape-scale analysis to promote a plantation project. Analysis of policy implications is made in the context of national legislation, socio-economic, institutional and environmental issues. The role of research and communication to improve decision-making processes at all scales are also examined. At least three wood species (Samanea saman, Acacia mangium and Gmelina arborea) with a total of 37 sites and an aggregate area of approximately 26,600 ha (266 km2), were found to be potentially able to sustain a local development initiative for all five municipalities located in southern Aragua state. In terms of implementation, small-scale forestry (SSF) is viewed as a new policy shift for forest management according to the new national forest legislation where local development is a central element. SSF faces several constraints and faces a wide variety of political issues. Critical among these issues are: (a) how SSF approaches deal with legislation and land tenure regulations; (b) the creation of community-based forest enterprises based on simplified management plans, (c) a broad assessment of potential ecosystem services delivered by forest plantations; and (d) improving communication of research for decision-making. Decentralization and institutional strengthening are identified as two basic conditions for pursuing sustainable management.

Fiber saturation point (FSP) of several Indonesian commercial wood species was studied comprehensively. Five wood species namely sengon (Paraserianthes falcataria), gmelina (Gmelina arborea) , nangka (Arthocarpus heterophyllus), manii (Maesopsis eminii), and mangium (Acacia mangium) from plantation areas closed to Bogor Agricultural University (IPB) campus were used as the sample. From each species, one normal tree was selected then cut, and one hundred and twenty small healthy blocks of (1 x 1 x 0.5) cm 3 were extracted randomly and utilized for specific gravity (SG) and wood shrinkage -green to air dry and to oven dry conditions- measurement. FSP was then measured as a ratio of total volumetric shrinkage and the SG. It was showed that FSP was affected by species namely extractive content. In all species studied, average value of FSP was below 30%. FSP of sengon, gmelina, nangka, manii, and mangium in average was 26.41%, 16.92%, 14.49%, 22.31%, and 23.94%, respectively.