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- Volume 2001, Issue 190, 2001
Southern African Forestry Journal - Volume 2001, Issue 190, 2001
Volume 2001, Issue 190, 2001
Author Neville P. DenisonSource: Southern African Forestry Journal 2001, pp 1 –2 (2001)More Less
Extracted from text ... Southern African Forestry Journal - No. 190, March 2001 1 GUEST EDITORIAL Tree Improvement: What has South Africa achieved? For some 50 years world forestry has acknowledged South African foresters for their pioneering work in silvicultural and management practices. Their high standards of plantation forestry are well known. Many systems researched and developed in South Africa have been applied to world forestry practices on all the major continents. It is no surprise therefore that Minister Ronnie Kasrils could proudly inform the IUFRO Working Party that South Africa has the largest plantation area of any country, certified by the Forestry ..
Source: Southern African Forestry Journal 2001, pp 3 –4 (2001)More Less
Extracted from text ... Southern African Forestry Journal - No. 190, March 2001 3 Foreword Editor The contributions included in this Dedicated Edition of the Southern African Forestry Journal are all Papers presented at the International Union of Forestry Research Organisations (IUFRO) Working Party 2.08.01 Conference "Forest Genetics for the Next Millennium" held in Durban RSA from 8 to 13 October 2000. The following extract from the conference Welcome Address by the IUFRO President - Professor Jeff Burley - is of interest and relevance to all. "The question of genetic modification of crop plants is an exceptionally critical, political and public issue at ..
Text of speech by Minister Ronnie Kasrils MP to IUFRO Conference on "Forest genetics for the next millennium" Durban 8 to 13 October 2000Author Ronnie KasrilsSource: Southern African Forestry Journal 2001, pp 5 –8 (2001)More Less
Extracted from text ... Southern African Forestry Journal - No. 190, March 2001 5 Text of speech by Minister Ronnie Kasrils MP to IUFRO Conference on "Forest genetics for the next millennium" Durban 8 to 13 October 2000 I am pleased to see how many of you have travelled to participate in this conference, from so many parts of the world. It is good to see how many papers are to be presented by researchers from South Africa, a good sign of health in the forest research community! I am also pleased to see a keynote paper on African Acacias. It is high time ..
Author R.D. BarnesSource: Southern African Forestry Journal 2001, pp 9 –18 (2001)More Less
There are 129 <i>Acacia</i> species in Africa. They are intermediate in plant succession and colonize degraded land. They restore fertility and can be maintained indefinitely in agricultural systems. They provide many benefits but are disliked for their thorns and invasiveness. Seed was collected across the ranges of <i>Acacia erioloba</i>, <i>A. karroo</i>, <i>A nilotica</i>, <i>A.senegal</i>, <i>A. tortilis</i> and <i>Faidherbia</i> (formerly <i>Acacia</i>) <i>albida</i>. Screening trials indicated that, with selection, all had potential both inside and outside their natural ranges. Subsidiary studies showed that some acacias obtain their nitrogen from groundwater rather than from the atmosphere, that they can produce more crude protein per hectare than a grain crop, that there are annual rings in the wood, and that gum arabic could be a lucrative cash crop. Farmers will resist planting acacias until the benefits can be translated into cash. The challenge for breeders in the new millennium is to produce trees that are inherently so good that they sell themselves to the farmer.
Author W.S. DvorakSource: Southern African Forestry Journal 2001, pp 19 –24 (2001)More Less
Extracted from text ... Southern African Forestry Journal - No. 190, March 2001 19 Positioning tree improvement programs to utilize advances in new technologies W S Dvorak Research Professor of Forestry & Director: CAMCORE North Carolina State University INTRODUCTION Forestry will be characterized by many changes in early part of the 21st century. Forest industries will continue to merge in order to capture greater percentages of the wood and paper market. For example, if International Paper Company acquires Champion International Corporation the new group will control 19% of the North American coated paper market (Pulp & Paper Week, 2000). Success of such business ..
A manager's view of tree improvement - towards designer fibres : maximising value from applied tree improvementAuthor C. HarvettSource: Southern African Forestry Journal 2001, pp 25 –30 (2001)More Less
Extracted from text ... Southern African Forestry Journal - No. 190, March 2001 25 A manager's view of tree improvement - towards designer fibres: maximising value from applied tree improvement C Harvett Mondi Forests "There is nothing mysterious or difficult about tree improvement. It consists mostly of the use of common sense in forestry management, looked at from the point of view of the basic biological organism - the tree" (Zobel and Talbot, 1984). In sharing this quotation, a number of salient points emerge: 1) it is important to acknowledge that forest genetics is a young science 2) its institutional origin dates back ..
Author T. WhiteSource: Southern African Forestry Journal 2001, pp 31 –42 (2001)More Less
This paper describes some recent developments that affect the way forest geneticists think about breeding strategies for forest trees. The topics are grouped into several categories : (1) General Concepts ; (2) Breeding Population Size ; (3) Breeding Population Structure ; (4) Management of the Breeding Population ; and (5) Incorporating New Technologies in Tree Improvement Programs. The last major section on new technologies highlights : (1) The increasing importance of hybrid breeding in tree improvement programs : (2) The potential of somatic embryogenesis as a biotechnology leading to clonal forestry for some commercially-important species ; and (3) The need for forest tree breeders and molecular geneticists to work together to incorporate promising new technologies into applied breeding programs.
Source: Southern African Forestry Journal 2001, pp 43 –52 (2001)More Less
CAMCORE has visited 33 populations of <i>Pinus caribaea</i> var. <i>hondurensis</i> in Belize, Guatemala, Honduras, El Salvador, Nicaragua, and Quintana Roo, Mexico. Seed collections have been made in 29 provenances from 1, 325 mother trees. A total of 21 provenances and sources of <i>Pinus caribaea</i> var. <i>hondurensis</i> were tested in 48 provenance / progeny trials in Brazil, South Africa, and Venezuela. Growth rates in Brazil and Venezuela were quite promising, and were less encouraging in Colombia. In Brazil and Venezuela, heights were around 12 m and mean DBH was around 18 cm at age 8. Growth in Colombia was substantially slower, with mean height less than 8 m at age 8, and mean DBH around 13 cm. Assuming 1111 stems / ha with 85% survival, these growth rates correspond approximately to volumes (outside bark) of 14 - 15 m<sup>3</sup> of wood/ha/year on sites in Brazil and Venezuela, and 4 - 5 m<sup>3</sup> / ha / yr in Colombia. Since these data represent the mean of unimproved material from all provenances, substantially larger values should be expected from selected material from the best provenances planted on suitable sites.<br> Forking and foxtailing percentages were high in some tests in Brazil and Venezuela. There were generally higher incidences of foxtailing in Venezuela (greater than 25% at ages 5 and 8) than in Brazil (7 to 13% at ages 5 and 8). Forking was more similar, with means around 30% in Brazil and Venezuela.<br> Provenances had relatively similar growth rankings in the different countries, with a Type B provenance correlation of 0.59. BLUP predictions of provenance effects were made for Brazil, Colombia and Venezuela. The best native provenances were Limon (Honduras) and Melinda (Belize), and Guanaja (Honduras) also performed well. Improved sources from Queensland Forest Research Institute (Australia) and South African Forest Research Institute were 6 to 12% better than the mean of the unimproved provenances, depending on the country where they were planted.
Source: Southern African Forestry Journal 2001, pp 53 –60 (2001)More Less
Tree improvement is central to increasing plantation productivity per unit land area in many countries that rely on an exotic fast grown plantation resource as a source of wood and fibre. In order to achieve an acceptable return on the investment made in tree breeding, it is important that material be deployed with both good husbandry and on sites where the genetic potential can be expressed. Apart from the obvious breeding and propagation of genetically improved material, such a deployment strategy has three components.<br> 1. A site classification system to determine the geographic distribution of environmental variables significant to site quality and tree growth potential<br> 2. The development of cultural best operating practices to promote growth of improved material, particularly before canopy closure<br> 3. A system of measurement to measure the success of operational deployment of genetic gain and related future forest productivity<br> The concept of operational gain integrates genetic improvement with cultural practices and site growth potential as a measure of the capture of genetic gain at an operational level. In this paper, initial results from a trial series testing the interaction of different levels of genetic improvement in eucalypts, with different levels of silvicultural after care over two sites are used to quantify the relative importance of each of the three components.
Author C.R.E. ClarkeSource: Southern African Forestry Journal 2001, pp 61 –66 (2001)More Less
<i>Eucalyptus</i> clones, the ultimate exploitation of genetic variation, are perceived to be the ideal raw material for the pulp mill but is this really true? Their attributes include uniformity, superior pulp properties and faster growth while their only limitation is lack of the natural genetic variation which provides protection against adverse elements. This shortcoming, unless managed, is likely to have a dramatic impact on a mill. Commercial compartments of clones rarely exceed 100ha and are more commonly less than 50ha. The maximum that is planted to an individual clone in one year is 200ha. At an assumed production of 200t / ha this implies that parcels of up to 10, 000t of timber (but more often less) from a single genetic entity will arrive at the mill gate at the same time. Dramatic differences between clones are likely introduce more variation in the form 'slugs' than is experienced with seedlings where the variation is more of a continuous nature. The ten <i>E. grandis</i> hybrid clones used commercially by Sappi Forests have been evaluated for wood and dissolving pulp properties across a number of trial sites. Although wood and pulp properties varied between trees within clones, most of the variation was found to occur between clones and, as expected, clones were more uniform than seedlings. Dissolving pulp yield of clones varied from 43.8 to 45.6%, viscosity from 41.4 to 69.8cps and brightness from 43.7 to 50.7. Wood density was found to vary between clones from 460 to 570kg / m<sup>3</sup>, fibre diameter from 12.05 to 14.49:m and cell wall thickness from 2.40 to 2.64 : m. Differences in wood and dissolving pulp properties between and within clones are compared here with <i>E. grandis</i> seedlings, the impacts on daily running of a dissolving pulp mill are discussed and suggestions are provided for management of clones in the mill to make best use of their unique properties.
Source: Southern African Forestry Journal 2001, pp 67 –72 (2001)More Less
The extensive development of plantation forestry in the tropics and Southern Hemisphere marks one of the great industrial successes of the 20th Century. Early experience led to the discovery that certain trees, although not particularly impressive in their areas of origin, can grow rapidly in exotic situations. More importantly, they are sufficiently genetically malleable to become outstanding plantation species through breeding. Perhaps the best examples of such trees are <i>Pinus radiata</i> and <i>Eucalyptus grandis</i>. By the early 1960's, diseases and pests were recognised as two of the most important threats to exotic plantation forestry. It was realised that separation of the crop from its natural enemies was responsible for the initial outstanding productivity of exotic plantation forestry. Gradually, new pathogens have been introduced in plantations in the tropics and Southern Hemisphere. The impact of these problems has been offset by new technologies that enhance the production of elite planting stock. During the course of the 21st Century, we will experience the emergence of many new strategies to cope with disease and insect pests in intensively managed and genetically modified plantations. The impact of DNA based technologies that enhance breeding will be one of the first developments, followed by the deployment of transgenic trees and microbes. The rapid emergence of DNA based technologies will bring tremendous opportunities to forestry, including its capacity to deal with pests and diseases. However, early experiences are likely to also be beset with problems. These will include a negative perception of transgenics by environmental action groups and the public. Successful forestry will, however, rest on persistence and patience while problems are addressed. Winning industries will be those that have harnessed new opportunities and that have developed the strategies to capitalise on these when concerns linked to safe deployment have been addressed.
Evolutionary relationships of Slash Pine (Pinus elliottii) with its temperate and tropical relativesSource: Southern African Forestry Journal 2001, pp 73 –78 (2001)More Less
llozymes in bud tissue and monoterpene contents in xylem oleoresin of slash pine (<i>Pinus elliottii</i>) were analyzed from populations across the natural distribution, as well as those from other species in the AUSTRALES pines. Allozyme diversity measures of slash pine were similar to those found in other southern pines. The two slash pine varieties, the slower-growing south Florida variety (var. <i>densa</i>) and the more commercial "typical" variety (var. <i>elliottii</i>), were not separated in the cluster analysis of allozymes. Variation was continuous from south to north in Florida in slash pine, with no distinct transition between the two varieties. The monoterpene data also showed continuous variation between the two slash pine varieties. Expected heterozygosity declined from south to north, supporting the hypothesis that slash pine resided in a Pleistocene refugium in south Florida or the Caribbean, migrating northward at the close of the ice age. Allozyme frequencies as well as monoterpene compositions of slash pine and its AUSTRALES relatives showed a very close relationship between slash pine and Bahamian Caribbean pine (<i>P. caribaea</i> Morelet var <i>bahamensis</i>).
Alternative eucalypt species for Zululand : seven year results of site : species interaction trials in the regionAuthor R.A.W. GardnerSource: Southern African Forestry Journal 2001, pp 79 –88 (2001)More Less
The ICFR initiated a search for alternative eucalypt species for the Zululand Coastal Plain region during 1992 by establishing a series of site: species interaction trials in the area. Sixteen pure species (seedlings), one <i>E. grandis</i> intra-specific clone and five inter-specific hybrid (<i>E. grandis x either camaldulensis</i> or <i>urophylla</i>) commercial clones were planted at three sites ranging in climatic condition from warm and wet in the south to hot and dry in the north. Final measurements, assessments and wood-sampling for pulping properties was carried out during 1999. These results together with relevant recommendations are discussed in this paper. On a growth, disease-resistance and pulpwood-quality basis, the top performing pure species at the southern (highly productive) site at Terranera were <i>E. longirostrata</i> and <i>E. pilularis</i>, and on the drier, more marginal sites at Teza and False Bay, <i>E. henryi</i>, <i>E. citriodora</i>, <i> E. longirostrata</i> and <i>E. tereticornis</i> gave impressive results.
Prospects of eucalypt species, including interspecific hybrids from South Africa, for hardwood plantations in marginal subtropical environments in Queensland, AustraliaSource: Southern African Forestry Journal 2001, pp 89 –94 (2001)More Less
In Australia, there has been rapid expansion in recent years of commercial plantations of hardwood timber species, especially of <i>Eucalyptus</i> and <i>Corymbia</i>. In tropical and sub-tropical Queensland the land most likely to be readily available for this planting is in the marginal 650-1000 MAR zone where, potentially, millions of hectares could be planted on cleared land. Optimal forestry plantation practice requires matching of taxa (species-provenances-hybrids) and sites. However, experiment-based identification of taxa with commercial potential has not been accomplished for many regions in this rainfall zone of Queensland. In Brazil, China and South Africa, large viable plantation estates have been developed on marginal lands through use of hardy, high-yielding interspecific eucalypt hybrids (Eldridge et al. 1993). Eucalypt hybrid breeding is in its infancy in Queensland so the potential exists to accelerate the identification of superior hybrids through introduction and testing of material developed elsewhere. Based on this overseas experience, bulk seedlots of selected eucalypt hybrids have been introduced, in strict accordance with quarantine requirements, and are now being tested against <i>Eucalyptus</i> and <i>Corymbia</i> species and provenance controls in key regions of Queensland and northern NSW.<br> This paper presents two-year results for three trials in sub-tropical Queensland, indicates the taxa with fastest early growth and considers the potential and suitability of several eucalypt hybrids (seedlings) to marginal sites in Queensland.
Source: Southern African Forestry Journal 2001, pp 95 –98 (2001)More Less
Extracted from text ... Southern African Forestry Journal - No. 190, March 2001 95 Collection and conservation of Pinus maximartinezii, a rare and endangered pine species J L Romero1, T K Stanger2 and W S Dvorak3 1. CAMCORE Technical Manager, 2. Sappi Forests Research and CAMCORE Graduate Student, 3. CAMCORE Director INTRODUCTION Pinus maximartinezii Rzedowski is a rare pinyon pine known to occur naturally on only one site on the Cerro de Pi?ones, in the Sierra de Morones, near the town of Juchipila, in southern Zacatecas, Mexico (21 ?? 21' N, 103 ??13' W). P. maximartinezii has been considered one of the most ..
Indirect genetic selection of end-products wood properties : a method suitable for both tropical and temperate forest treesSource: Southern African Forestry Journal 2001, pp 99 –104 (2001)More Less
Extracted from text ... Southern African Forestry Journal - No. 190, March 2001 99 Indirect genetic selection of end-products wood properties: a method suitable for both tropical and temperate forest trees P Rozenberg1, A Franc, G Chantre and V Baonza 1INRA, Station d'Am?lioration, G?n?tique et Physiologie Foresti?res, BP 20619 Ardon, 45166 Olivet Cedex, France Tel: +33 (0)2 38 41 78 73, Fax: +33 (0)2 38 41 78 79, Email: firstname.lastname@example.org INTRODUCTION Trees in genetic tests are often valuable plant material that can't be felled. Wood density can be nondestructively measured on increment cores at a quite low cost. This is not the case of ..
Source: Southern African Forestry Journal 2001, pp 105 –114 (2001)More Less
This paper reports on progress made in the development and implementation of a stand level wood quality grading system for <i>P. patula</i> identified for processing in Mondi Merebank's stone ground wood and thermo-mechanical pulp lines. The grading system stratified the resource using fiber collapsibility as the selection criteria.<br> The paper evaluates the impact of the grading system on the process parameters and the basic characteristics of pulp produced by the different pulp lines. The grading system was found to have a positive impact on desired pulp quality criteria.<br> Variability inherent in the resource and the production process declined significantly upon implementation of the grading system. The results indicate the level of improvement that can be realized from a simple wood quality grading system. It is anticipated that a more detailed understanding of factors impacting on wood and pulp characteristics, and resource and process variation will support a process of continuous pulp quality improvement.<br> This work was co-sponsored by Mondi Forests, Mondi Merebank and the CSIR.
Author Richard BarnesSource: Southern African Forestry Journal 2001, pp 115 –118 (2001)More Less
Extracted from text ... Southern African Forestry Journal - No. 190, March 2001 115 Round-up for IUFRO Durban 2000 by Dr Richard Barnes INTRODUCTION The Minister in his address highlighted the importance of forestry as one of the largest rural investments in South Africa. The country also has the largest plantation area in the world that has been certified as sustainably managed. The forest manager was exhorted to maximize return on the investment in forestry including the efficient use of water and the alleviation of poverty; the researcher was exhorted to direct his research towards the manager's needs to accomplish these goals. I ..