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The influence of climate changes on Central European forests with an emphasis on Slovenia
2022 - IRG/WP 22-50368
When forests are managed sustainably, they play an essential role in protecting climate and biodiversity. They protect soils and water resources, provide livelihoods, and contribute to the well-being of rural and urban communities. European forests are multifunctional and provide a range of ecosystem services. These include the production of renewable materials that can replace materials with a la...
J Gričar, L Krajnc, M Westergren, S Rus, H Kraigher


Effects of seed origin and site on both wood density and longitudinal fluid uptake of Sitka spruce (Picea sitchensis (Bong.) Carr.) with height in the tree grown in the United Kingdom
2002 - IRG/WP 02-40226
The variation in density and longitudinal fluid uptake was investigated in short specimens of wood taken from eight seed origins of Sitka spruce trees grown at two sites in the UK. Five trees of each seed origin at each site were sampled at three heights (1, 2 and 3 m above ground level). The density of the samples decreased with increasing height within the stem. This corresponded with increasin...
I Usta, M D C Hale


Analysing the characteristic role of moisture content for drying and fluid flow in Sitka spruce. - Part 1: The drying process of sapwood and heartwood of two different thickness of Sitka spruce using a kiln. - Part 2: Effects of moisture content on longitudinal permeability of Sitka spruce in vertical variation of the tree
2000 - IRG/WP 00-40173
The characteristic role of the moisture content in Sitka spruce (Picea sitchensis (Bong.) Carr.) that grown in the United Kingdom was examined by this study on the basis of (1) the reduction of moisture content in two different thickness of sapwood and heartwood by kiln drying process, and (2) the effects of moisture content to the longitudinal void volume filled of tanalith-C by the full-cell pro...
I Usta


Termiticidal chemicals derived from tropical tree resins
1991 - IRG/WP 1477
To test the hypothesis that defensive chemicals protect tropical primary forest trees against biological attack, a bioassay and fractionation program was conducted in Indonesia. Fresh dipterocarp resins were fed in no-choice tests to Neotermes dalbergiae termites on 4.5 cm filter papers, or tested for inhibition of fungal growth. Fractionation of biologically active resins via flash column chromat...
A Messer, K McCormick, D Richardson, Sunjaya, H Hagedorn, J Meinwald


The effects of density on vertical variation of permeability of Sitka spruce within tree
2000 - IRG/WP 00-40156
Tree improvement of Sitka spruce is a combination of silviculture and tree breeding aimed at producing higher quality products including increased growth rate and timber yield, and wood density. It is useful to know annual ring structure and density distribution when studying the quality of wood, grading it, or determining how the wood structure affects residual flow in softwoods. Since density is...
I Usta.


Study of the natural durability and impregnability of a metropolitan species of tree
1986 - IRG/WP 2261
The current and predictable evolution of construction timber supply conditions is motivating research for a more efficient utilization of native woods. It is now important to determine statistically reliable impregnability values on a national scale, and to evaluate the natural durability of woods recently introduced in France, or economically important native woods....
M E Mathieu


The chemical analysis and biological evaluation of wood extractives as potential timber preservatives
1995 - IRG/WP 95-30090
Work involved the biological performance of water and organic solvent soluble extractives of four naturally durable wood species, namely; Matumi, Tamboti, Sneezewood and the Turpentine tree. These timber species are known to be naturally durable against termites and fungi (±25 to 35 years). The extractives were evaluated against termites and fungi using impregnated pine pencil stakes in field tes...
P Turner, D Conradie


Forest management policies and timber supplies in British Columbia
1997 - IRG/WP 97-10244
British Columbia has a huge wealth of timber resources, currently exceeding 7 billion m3 of mature timber on about 43 million ha classified as productive forest lands. That land area also supports a current volume of over 2 billion m3 of timber in immature stands. How much of the volume will be made available as an annual timber supply for the forest industry is dependent upon a set of policies go...
R B Addison


Natural durability, density and extractive contents of 42 wood species of Bangladesh.
2003 - IRG/WP 03-10490
Natural durability, density and major extractive contents of 42 lesser used or unused wood species of Bangladesh have been studied. Correlation analysis between these properties has been performed. It has been shown that natural durability of these species neither explained by water soluble nor by alcohol benzene extractive contents. Density has a weak but significant positive correlation with dur...
S Akhter, K Akhter, S C Das


Evaluation of copperised Cashew nut shell liquid and Neem oil as wood preservatives
2005 - IRG/WP 05-30368
An effort has been made to develop eco-friendly wood preservatives using naturally available plant by-products with less toxicity. Copper was incorporated into Cashew nut shell liquid (CNSL) and Neem seed oil. Rubber wood samples were treated with these solutions employing dipping and pressure techniques in 3 different levels. These samples have been evaluated to find out the effectiveness as wood...
D Venmalar, H C Nagaveni


Über Hausbock Hylotrupes bajulus (L.), (Col., Cerambycidae), in Laubholz: Versuche mit Laubholzarten, Prüfung der Wirkung von Ligninstoffen und von Ginkgo biloba, Beobachtungen an Hesperophanes. [On House-longhorn Beetle Hylotrupes bajulus (L.), (Col., Cerambycidae) in hardwood: Investigations with several hardwood-species, tests on activity of lignin components and Ginkgo biloba, observations on Hesperophanes]
1982 - IRG/WP 1144
Hylotrupes bajulus-larvae feed and develop in softwoods, hardwood acts as a feeding poison. The reason for this is still little known. According to literature some observations contradict this established opinion and the question was raised, whether the colour-strain scutifer (= lividus) is able to live in hardwood. Testing ten European and tropical hardwood-species (following the DIN-EN test proc...
S Cymorek


Decay resistance of Siberian larch wood against brown rot fungus. - Part 3. The variation between plus trees and their grafted clones
2000 - IRG/WP 00-10350
The aim of the study was to estimate the variation in the decay resistance of Siberian larch (Larix sibirica Ledeb.) wood using mature plus trees and their grafted clones. Samples were collected with an increment core borer from 11 original plus trees and their 25-year-old grafted seed orchard clones. A typical brown rot fungus, Coniophora puteana (Schum. ex Fr.) Karst. (BAM Ebw. 15), was used as ...
H Viitanen, L Paajanen, M Venäläinen, A Harju, P Velling


Genetic Engineering in tree breeding
1998 - IRG/WP 98-10294
The genetic improvement of forest trees by classical breeding is a slow process in comparison with that of annual crops. Tree breeding however is of great importance and has led to trees with better growth characteristics and better disease resistance. An important wood characteristic which has been neglected in breeding programs is wood durability. The durability of the wood will determine for wh...
J Van Doorsselaere, H Beeckman, M Van Montagu, W Boerjan


Composition of urushiol and cardanol from Japanese lacquer tree and related origins
1991 - IRG/WP 3667
Wood may be protected against insects and weathering based on the paints. Japan has been used to protect wood from weathering, insects, checking that ordinarily develop when unprotected wood is exposed to the weather. Japaned wood gives a hard, durable, various gloss especially black. The yield of culture-urus hiol obtained from Japanese lacquer tree (Rhus vermiciflua Stokes) was 0.6% based on the...
Y Inoue


Effect of test methodology on seed germination using filter paper and soil as substrates
1994 - IRG/WP 94-50029
Tomato, cucumber and grass seeds were used to examine the influence ot two wood preservatives, chromated copper arsenate (CCA type C) and ammoniacal copper quat (ACQ tvpe B) in seed germination studies. Two methodologies, using contaminated filter paper and contaminated soil as substrates, were investigated to generate the comparison results. The results from these studies suggest that the test su...
L Jin, A F Preston


The use of fumigants for controlling decay of wood: a review of their efficacy and safety
1989 - IRG/WP 3525
Volatile agricultural chemicals (fumigants) such as chloropicrin (trichloronitromethane) and sodium n-methyldithiocarbamate have been used in the United States for controlling internal decay of large dimension wood products for over 20 years. This usage has been concentrated in the electric utility industry, but fumigants are increasingly applied to protect bridge timbers, marine piling, and even ...
J J Morrell


Supply of wooden transmission and telephone poles in Tanzania: Problems and possible solutions
1987 - IRG/WP 3424
The eucalypts which have been used widely for utility poles for more than 30 years have dwindled remarkably from traditional supply areas. Consequently, pole-using authorities are considering importing poles from abroad. This alternative is considered unrealistic and costly. The aims of this paper are: - to dispel fears of pole scarcity and to show that an abundant resource of a variety of tree sp...
K K Murira, S A Diwani


Wood preservation in Nigeria - Its increasing relevance, observed constraints and potential as a forest conservation option
1992 - IRG/WP 92-3732
The paper discusses the demand and supply of wood and wood products in Nigeria and points out that in view of the large population (88 million) and search for wood for housing and furniture, the demand exceeds supply. There is great shortage of industrial and domestic woods resulting in underutilization of installed machineries in forest industries and low profit margin. Under this prevailing cond...
M A Odeyinde, S C Ifebueme


Tree crown architecture: a tool for decay resistance evaluation
2013 - IRG/WP 13-10793
The variability of natural durability contributes to the bad perception of some wood end-users. In our search, we need to adjust our methods and strategies to estimate natural durability and extract higher value from wood resources. Architectural analysis is essentially a detailed, multilevel, comprehensive and dynamic approach to plant development. Numerous biological process which impact some wo...
N Amusant, J-B Anouhé Say, A Amissa, J Beauchène, F Niamké, E Nicolinni


Needs for wood durability research on planted tree species in the tropics
2008 - IRG/WP 08-10651
The area of forest plantation has been expanding especially in tropical Asia since 1990’s. Most of them are developed for pulp and paper industries and planted with fast growing trees. It is expected that wood from those fast growing trees are also used for value added products such as sawn timber. In order to promote the utilization of fast wood as the resource of value added products, natural...
K Yamamoto, T Toma, Ngo Duc Hiep, Nguyen Trong Nhan


A review of Sitka spruce (Picea sitchensis (Bong.) Carr.) as its Importance and Breeding
2010 - IRG/WP 10-10717
Foresters tend to concentrate on those species which are the easiest to handle silviculturally, and which will produce the greatest volume of generally useful wood in the shortest time. Sitka spruce (Picea sitchensis (Bong.) Carr.), which is a softwood species from the western seaboard of North America with a range extending from southern Alaska to northern California, is one of the pioneer specie...
I Usta, R Despot


Chapter 4 - Propagation of bamboo
2007 - IRG/WP 07-10635-04
The cultivation and propagation of bamboos are very essential to meet various human needs and environmental requirements. Different methods of propagation and regeneration of bamboos have been described in this chapter. The possibility of propagation through seeds are restricted and limited because of its inadequacy and non-viability. Due to this natural obstacle bamboos are predominately pr...
A K Lahiry


Seed oil and defatted cake proximate composition of non timber product Annona squamosa (Annonaceae) grown in Benin
2012 - IRG/WP 12-30607
Annona squamosa L. is a small tree which grows wild in many places in the tropical regions, locally called “xwingle” in Benin. Its produces edible fruits, typically globular or heart-shaped which are highly appreciated and the seeds are not used. In the course of work about identifying new oil sources from a large number of oil bearing seeds grown in Benin, we report here on the chemical compo...
T S Djenontin, J Dangou, P Lozano, D Pioch, D C K Sohounhloue


Treating Bambusa vulgaris with neem seed oil against basidiomycetic biodegradation
2012 - IRG/WP 12-30608
Realising maximum benefits from bamboo stems/culms in Nigeria are presently constrained by their almost non-acceptance for applications in most structural and construction purposes, except in comparatively low quality and some temporary applications, such as scaffolding, owing to their susceptibility to easy destruction by agents of biodegradation as a result of their poor inherent natural durabil...
A A Erakhrumen


Comparison of moisture loss and its increment during the rehearsal process based on natural drying and water soaking application with or without sealing the trial discs of Common black poplar (Populus nigra L.)
2013 - IRG/WP 13-40639
This study was subjected to be set up to prove the pattern of moisture loss and moisture increment within the same wood samples prepared as the discs (30x23±3 cm diameter) with or without the bark intact during drying and in the duration of the water soaking application. In this concept, wood was exemplified by Common black poplar (Populus nigra L.) of the five 12 year old trees that are grown in...
I Usta


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