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Wood trade is strongly dependent on global economic conditions. In Africa, the market for tropical wood also has dynamic changes.In Mozambique, the international demand for wood comes mainly from emerging economies such as China and India. Almost 70 %of the country is still covered by forests and other woody vegetation. There are many species with favorable properties for woodcommerce, although, at present, this is restricted to a few species. We analyzed the wood anatomy of Acacia nigrescens, Combretumimberbe, Icuria dunensis, Pericopsis angolensis and Sterculia appendiculata and comment about properties and potential use basedon their anatomical composition. In general, the species presented wood diffuse pores, simple perforation plates, alternate intervesselpits, deposits in vessels; abundant axial parenchyma; multiseriate rays, very thick-walled fibers and mineral inclusions. Based onanatomical characteristics, the studied species have great potential for use in panels industry, furniture, floor, structures and craftwork., El comercio de madera depende en gran medida de las condiciones económicas globales. En África, el mercado de las maderas tropicalestambién tiene cambios dinámicos. En Mozambique, la demanda internacional de madera proviene principalmente de las economíasemergentes como China e India. Casi el 70 % del país está todavía cubierta por bosques y otra vegetación leñosa. Hay muchas especiescon propiedades favorables para el comercio de madera, pero en la actualidad esto está restringido a unas pocas especies. Se analizó laanatomía de la madera de Acacia nigrescens, Combretum imberbe, Icuria dunensis, Pericopsis angolensis y Sterculia appendiculatay se comenta las propiedades y el uso potencial en función de su composición anatómica. En general, las especies tienen porosidaddifusa, placas de perforación simple, punteaduras intervasculares alternas, depósitos en los vasos; parénquima axial abundante; rayosmultiseriados, fibras de paredes muy gruesas e inclusiones minerales. Según las características anatómicas, las especies estudiadastienen un gran potencial para uso en la industria de paneles, muebles, pisos, estructuras y artesanía.

The objective of this study was to evaluate the natural durability of five lesser-utilized wood species from Mozambique. Both laboratory methods and field tests were applied for assessing wood decay of muanga ( Pericopsis angolensis ), metil ( Sterculia appendiculata ), namuno ( Acacia nigrescens ), ncurri ( Icuria dunensis ), and ntholo ( Pseudolachnostylis maprounaefolia ). Laboratory tests involved soft-, brown-, and white-rot fungi and termites. Heart- and sapwood of ncurri and ntholo were exposed in above-ground field tests; additionally, all species were exposed to in-ground contact tests. The results indicated that namuno, muanga, ncurri, and ntholo are resistant to soft-, brown- and white-rot fungi and the termite species Reticulitermes grassea and Mastotermes darwiniensis . Comparatively, soft-rot caused more severe decay on the studied wood species than did basidiomycete fungi. The brown-rot fungi Coniophora puteana , Gloeophiyllum trabeum , and Postia placenta caused less decay on the tested species than did the white-rot Trametes versicolor . Metil was not resistant to any of the mentioned hazards. Therefore, this species is not recommendable for exterior use if untreated.

This study investigated the relationship between tool wear and some chemical and physical properties for four different Mozambican lesser known tropical species,: Pseudolachnostylis maprounaefolia (ntholo), Sterculia appendiculata (metil), Acacia nigrescens (namuno) and Pericopsis angolensis (muanga). Tool wear is an important aspect for sawmilling and for the woodworking industry. For Mozambique, the utilization of available lesser known wood species will help to increase domestic industry and the economic usage viability of sustainable forest management. A set of experiments was performed on a shaper with a mechanical feed mechanism. Tools of a cemented carbide grade for woodworking were used, and the cutting parameters were fixed. Edge recession and tool wear radius were measured for monitoring tool wear. The wear mechanism was investigated using a scanning electron microscope. The experimental results showed that the chemical properties of the wood species have a great effect on tool wear. Wo...

Three lesser known wood species from Mozambique were studied to generate information for identification purposes and facilitate the introduction of these species into the wood working industry by assigning or widening the potential uses of these species. Selected anatomical features were used to predict some important wood properties, subsequently confirmed by measurements of both density and impregnability. Comparative wood anatomy showed that all three wood species have anatomical features typical for their genus after comparisons with their closest relatives. Both ntholo (Pseudolachnostylis maprounaefolia Pax) and muanga (Pericopsis angolensis Meeuwen) are diffuse-porous (with 14–24 and 16–20 vessels/mm2 respectively), have extractives in the heartwood vessels and thick-walled fibres, features consistent with good natural durability and strength respectively. Metil (Sterculia appendiculata K. Schum.) is also diffuse-porous with very wide vessels at much lower frequency (2), it lacks extractives in the heartwood vessels, and thin-walled axial and ray parenchyma constitutes the bulk of the ground tissue. This set of characteristics makes the wood light and satisfactory for construction purposes but highly vulnerable to biodegradation.

Mozambique is a country with vast forestry resources that include native wood species with high commercial value. Thus, the trade of timber as raw material, as well as wooden finished products are commercial options of considerable valuable for the country. This work presents information about anatomical characteristics, physical and mechanical properties and use of some native wood species from Mozambique, namely, Afzelia quanzensis, Androstachys johnsonii, Erytrophleoum suaveolens, Khaya nyasica, Pterocarpus angolensis, Milletia stuhlmannii and the emerging lesser-known species Pericopsis angolensis, Sterculia appendiculata and Sterculia quinqueloba. The study concludes that these Mozambican wood species are similar in several aspects. They are generally described as very hard, dense, having high mechanical strength and durable. The study also concludes that although the lesser-known wood species, S. quinqueloba, has similar properties to the traditionally used one, A. quanzensis, it is less used because of its poorly known properties and potential uses. Thus, further research to determine the properties and suitable end uses of other lesser know species is likely to be beneficial to the country.

Two new Hyphomycetes from Pericopsis angolensis leaf litter collected in Tanzania are described and illustrated. Endophragmiella africana sp. nov. is unique among those species of Endophragmiella p...

Ten compounds have been isolated from S. madagascariensis, generally in very small quantity and, where not previously known, their structures have been established by degradative and spectroscopic means, supported in two cases by synthesis. Three of these compounds, homopterocarpin (II; R = Me), demethylpterocarpin (I; R = H), and pterocarpin (I; R = Me) are known, whereas the remaining seven, 3-hydroxy-9-methoxyptero-carpan (II; R = H), 3-hydroxy-4-methoxy-8,9-methylenedioxypterocarpan (X), 3-hydroxy-4,9-dimethoxy-pterocarpan (XIII), 3,4-dimethoxy-8,9-methylenedioxypterocarpan (VII), 3,4,9-trimethoxypterocarpan (XI), 3,9-dimethoxypterocarp-6a-en (XIV), and 3,9-dimethoxy-6-oxopterocarp-6a-en (XVI; R = Me) have not been found previously in nature. The known 3,4,3′,5′-tetrahydroxystilbene and homopterocarpin have been isolated from P. angolensis.