The change in greenhouse operation and technology in the last 20 years has been unprecedented. Photoperiodic control, mist propagation, green house cooling, clean stock programs, CO injection, to name a few, have 2 all been inaugurated as regular greenhouse practices in this time. The introduction of new markets, new production centers, shifts in public attitudes, and the realization that greenhouse production is not simply growing crops, but the management of an enterprise in which people work, h ve combined to make this agricultural practice a challenging and rewarding vocation. The greenhouse grower, manager, and student who are training for this vocation have not had an up-to-date text book for many years. It has been our goal to bring both published and unpublished work together in this book, and to provide a bench mark from which we can continue to move forward. It is not until a process of writing a text begins that one fully realizes how far we have come-and where we need to go. It is with some sadness that we realize that this book is not likely to remain long as an expression of the state-of-the-art. We do not expect it to be easy reading; for new terms, new technology, and new ways of doing things are not always easy."

Cyril Hart's seminal work on woodland management and practices is back in this fourth edition, which covers a wealth of material including financial management, taxation, the integration of forestry and agriculture, silvicultural operations, grading of timber, valuations marketing, utilisation, non-wood benefits, saw-milling and nursery practice. A modern classic that has been a trusted companion to forestry students and experts for decades, Practical Forestry is a must-have for anyone interested in working in, managing or preserving Britain's lush and vital woodland areas.

Provided here is a comprehensive treatise on all aspects of dielectric properties of wood and wood products. The topics covered include: Interaction between electromagnetic field and wood. - Wood composition and dielectric properties of its components. - Measurement of dielectric parameters of wood.- Dielectric properties of oven-dry wood. - Dielectric properties of moist wood. - Effect of different kinds of treatment on dielectric properties of wood. - Dielectric properties of bark. - Dielectric properties of wood-based materials. - Recommendations for determination of dielectric parameters of wood based materials and for their use in calculations. Several appendices comprise reference data onthe dielectric characteristics of wood and wood-based materials in the wide range of frequencies, temperatures, and moisture content.

These are the proceedings of an Advanced Research Workshop (ARW), sponsored by the NATO Science Panel, entitled "Pest Control: Operations and Systems Analysis in Fruit Fly Management." The ARW was held in Bad Windsheim, Germany during the week of 5 August 1985. The purpose of the ARW was to bring together scientists who are interested in fruit fly problems, but who usually do not have an opportunity to speak with each other, for an intense week of interdisciplinary collaboration. In particular, the group present at the ARW contained a mix of biologists, field ecologists, mathematical modellers, operational program managers, economists and social scientists. Each group has its own professional meetings at which fruit fly problems are discussed, but the point of the ARW was to learn about the problem from the perspective of other fields, which are equally important for the ultimate management of the fruit fly problems. (A list of attendees follows this preface. ) It appears that the ARW successfully met its objective of bringing together a group for interdisciplinary considerations of the problems; I hope that the proceedings do as well. The ARW was structured with formal lectures in the mornings and workshops in the afternoons. For the morning lectures, four different topics were chosen: 1) basic biology and ecology, 2) trapping and detection, 3) control and eradication, and 4) policy issues. Each morning, one lecture from each area was presented.

th st On June 20 and 21 1985 the third workshop on "Azospirillum: Geneties, Physiology, Eeology" took place at the University of Bayreuth, West Germany, organized by the geneties department. There were about 80 partieipants, who eame from German research institutions, from other European eountries, from India, Egypt, North and South America. The former workshops had taken place in Bayreuth too in 1981 and 1983 respeetively, henee the organizers eould draw on the experienees then obtained. Azospirilla have, during the past 12 years, found an ever inereasing seientifie interest, beeause first, these soil baeteria earry the genetie information for binding moleeular nitrogen from the air, and second, they live in elose vieinity to the roots of grain erops and forage grasses. By exploi tation of these two properties, it is hoped to develop inoeulation proeedures in soils poor in nitrogen. The reports on the first afternoon foeussed, as aresult of the Bayreuth research interest, on genetie approaehes.

Throughout the world natural forest ecosystems have been, and are being massively disrupted or destroyed. The boreal forests of Canada are no more immune to man's intervention than the tropical rain forests of Africa, and the day is rapidly approaching when natural forest ecosystems, undisturbed by man, will be found only as remnants in national parks and other protected areas. Yet where they continue to exist these ecosystems are an extraordinarily rich, though relatively neglected source of data that illuminate many aspects of the classic theory of evolution. The subject matter of this book is not, however, confined to natural forest ecosystems. Forest ecosystems under varying degrees of management, and man made forests are also a rich source of information on ecological genetics. In general, however, it can be said that the published evidence of this fact has not yet significantly penetrated the botanical literature. All too frequently it is confined to what might be termed forestry journals. It is hoped that this book will to some extent redress the balance, and draw attention to a body of published work which not only provides a basis for the rational management and conservation of forest ecosystems, but also complements the literature of ecological genetics and evolution. The first draft of Chapters I to V was written in German by the senior author and translated by E. K. MORGENSTERN of the Canadian Forestry Service."

The world needs for food and fiber continue to increase. Population growth in the developing countries peaked at 2. 4% a year in 1965 and has fallen to about 2. 1%. However, in many developing countries almost half the people are under 15 years of age, poised to enter their productive and reproductive years. The challenges to produce enough food for this growing population will remain great Even more challenging is growing the food in the areas of greatest need. Presently the world has great surpluses of food and fiber in some areas while there are devastating deficiencies in other areas. Economic conditions and the lack of suitable infrastructure for distribution all too often limit the alleviation of hunger even when there are adequate supplies, sometimes even within the country itself. World hunger can be solved in the long run only by increasing crop production in the areas where the population is growing most rapidly. This will require increased efforts of both the developed and developing countries. Much of the technology that is so successful for crop production in the developed countries cannot be utilized directly in the developing countries. Many of the principles, however, can and must be adapted to the conditions, both physical and economic, of the developing countries.

The introduction of chain saws and tractors in the early 1950's marked the beginning of a change in tree harvesting techniques from the old manual methods to mechanized operations. It was followed by a rapid evolution both technically and systematically. Hence, the requirements for improved know ledge of operational efficiency also increased. Changing relations between Man, machines and environment brought about new experiences and awareness of a physiological and ergonomic nature. Improved knowledge of both machine technology and planning of work on a small or large scale has grown increa singly important for an efficient utilization of expensive machines and other equipment. The need for a textbook on tree harvesting techniques including expe riences made in recent years is enhanced. The book presented here is prima rily based on lectures given on the subject of Forest Techniques at the Faculty of Forestry at the Swedish University of Agricultural Sciences and after modifications also at the University of Nairobi (Kenya). Thus, the book is written primarily for students at the faculties and institutes of forestry. However, it is also useful for persons actively occupied in forest operations. The presentation of this book in its original Swedish version in 1972 created a considerable interest in the preparation of a condensed edition in English. Thus interest has been expressed in Finland, Norway, Holland, Canada, U.S.A., Brazil, Japan, Poland, Scotland and Yugoslavia."

This book focuses on sediments as a pollutant in natural freshwater and marine habitats, and as a vector for the transfer of chemicals such as nutrients and contaminants. Sediment-water research is carried out all over the world within a variety of disciplines. The selected papers cover three main topics relating to assessment and/or restoration of disturbed watersheds, sediment-water linkages in terrestrial and aquatic environments and evaluation of sediment and ecological changes in marine and freshwater habitats. Innovative research in both developed and less developed countries is included. Both fundamental research, insight into applied research and system management are covered. The volume will also appeal to readers involved in sediment geochemistry and dynamics, aquatic habitats, water quality, aquatic ecology, river morphology, restoration techniques and catchment management.

Since the first edition of our book "Tissue Culture in Fores try" in 1982 we have witnessed remarkable advances in cell and tissue culture technologies with woody perennials. In addition to forest biologists in government, industry, and universities, we now have molecular biologists, genetic engineers, and biochemists using cell and tissue cultures of woody species routinely. There fore, the time has come for an update of the earlier edition. In our present effort to cover new developments we have expanded to three volumes: 1. General principles and Biotechnology 2. Specific Principles and Methods: Growth and Development 3. Case Histories: Gymnosperms, Angiosperms and Palms The scientific barriers to progress in tree improvement are not so much lack of foreign gene expression in plants but our current inabili ty to regenerate plants in true-to-type fashion on a mas sive and economic scale. To achieve this in the form of an appro pr iate biotechnology, cell and tissue culture will increasing ly require a better understanding of basic principles in chemistry and physics that determine structural and functional relationships among molecules and macromolecules (proteins, RNA, DNA) within cells and tissues. These principles and their relationship with the culture medium and its physical environment, principles of clonal propagation, and genetic variation and ultrastructure are discussed in volume one."

Much research has been done recently, and more is now in progress, to increase the effectiveness under tropical conditions of methods which have been developed in Europe for preserving timber. This book attempts to bring together the results of some of these studies. I have not attempted to cover the tropical zones of Central and South America as this would have extended the book beyond its limits. But I am grateful to the authors who have contributed chapters dealing with the different aspects and solutions of the problems of the tropical areas of the Old World. The International Research Group for Wood Preservation (The I.R.G.) at its annual meetings in different countries has provided a valuable forum for cooperation in this developing field. Anyone concerned with the subject would be well advised to study the publications issued by this group. Their office is at Drottning Kristinas vag 47C S - 11428 Stockholm, Sweden. Although timber is a renewable resource there is every reason why it should not be wasted through premature decay or the ravages of termites etc., when effective measures for its preservation are available and, if correctly applied, can greatly reduce the cost of maintaining timber structures.

Drawing upon a wealth of past research and results, this book provides a comprehensive summary of state-of-the-art methods for empirical modeling of forest trees and stands. It opens by describing methods for quantifying individual trees, progresses to a thorough coverage of whole-stand, size-class and individual-tree approaches for modeling forest stand dynamics, growth and yield, moves on to methods for incorporating response to silvicultural treatments and wood quality characteristics in forest growth and yield models, and concludes with a discussion on evaluating and implementing growth and yield models.

Ideal for use in graduate-level forestry courses, this book also provides ready access to a plethora of reference material for researchers working in growth and yield modeling.

"

Providing a link between theoretical and applied aspects of plant nutrition and agriculture, this book introduces new concepts in plant nutrition. It shows how these can be applied in order to assess the nitrogen status in crops and to improve nitrogen nutrition through optimized N fertilization management. In this way economic benefits can be obtained, while at the same time preventing detrimental effects on the environment. The main agricultural crops - grasses, wheat, barley, Durum wheat, maize, sorghum, grain legumes and potatoes - are covered. The book will be an invaluable source for agronomists.

Research on the interactions of plants and phytopathogenic fungi has become one of the most interesting and rapidly moving fields in the plant sciences, the findings of which have contributed tremendously to the development of new strategies of plant protection. This book offers insight into the state of present knowledge. Special emphasis is placed on recognition phenomena between plants and fungi, parasitization strategies employed by the phytopathogenic fungi, the action of phytotoxins, the compatibility of pathogens with host plants and the basic resistance of non-host plants as well as cultivar-specific resistance of host plants. Special attention is paid to the gene-for-gene hypothesis for the determination of race-specific resistance, its molecular models and to the nature of race non-specific resistance as well as the population dynamics of plants and the evolution of their basic resistance.

The lntergovernmental Panel on Climate Change (IPCC) has recently summarized the state ofthe art in research on climate change (Climate Change 1995). The most up to date research findings have been divided into three volumes: * the Science ofClimate Change (working group I), * the Impacts, Adaption and Mitigation of Climate Change (working group II), and * the Economic and Social Dimensions ofClimate Change (working group III) There is a general consensus that a serious change in climate can only be avoided if the future emissions of greenhouse gases are reduced considerably from the business as usual projection and if at the same time the natural sinks for greenhouse gases, in particular that of CO , are maintained at the present level or 2 preferrably increased. Forests, forestry and forestry industry are important parts of the global carbon cycle and therefore they are also part of the mitigation potentials in at least a threefold way: 1. During the time period between 1980 and 1989 there was a net emission of CO from changes in tropical land use (mostly tropical deforestation) of 2 1. 6 +/- 1 GtC/a, but at the same time it was estimated that the forests in the northem hemisphere have taken up 0. 5 +/- 0. 5 GtC/a and additionally other terrestrial sinks (including tropical forests where no clearing took place) have been a carbon sink ofthe order of l. 3 +/- l.

Eeonomie plants range from those that are eommercially utilised by the industrial nations of the world to those that safeguard the survival of hunter-gatherer aboriginal eommunities. In a world of inereasing human and livestock populations, land and environment degradation, species loss and climatic change, it is becoming inerea- singly important to work for the sustainable management of the world's natural resourees. This is especially important for the arid and semi-arid regions where any abuse of the harsh environment is unforgiving. Plant resourees are especially important sinee they proteet the environment, provide habitats for both flora and fauna, and direetly or indireetly provide the resourees for man's survival. An understanding of how plants are adapted to survive is an essential tool for the better management of the environment. Sinee there are over 20000 useful plants in the arid and sem i-arid regions of the world, of which only a relative few have been even partially investigated, the writer makes no apologies for whieh plants have been included or ignored. All the plants mentioned in the introductory ehap- ters marked with an asterisk are diseussed more fully in Chapter 11.

Ex situ preservation of germplasm for higher plant species has been accom plished using either seeds or clones, but storage of these under typical condi tions does not provide the extreme longevities that are needed to minimize risk of loss. Costs of maintenance and regeneration of stocks are also high. Systems that provide virtually indefinite storage should supplement existing methods and it is within this context that cryopreservation is presented. The use of low temperature preservation was initially more a concern of medicine and animal breeding, and was expanded to plants in the 1970s. Sur vival after cryogenic exposure has now been demonstrated for diverse plant groups including algae, bryophytes, fungi and higher plants. If survival is com monplace, then the eventual application is a cryopreservation system, whereby cells, tissues and organs are held indefinitely for use, often in the unforeseen future. The increasing interest and capabilities for application could not have occurred at a more opportune time since expanding human populations have placed unprecedented pressures on plant diversity. This book emphasizes cry opreservation of higher plants and was initially driven by the concern for loss of diversity in crops and the recognized need that this diversity would be essential for continued improvement of the many plants used by society for food, health and shelter. The interest in cryopreservation has been expanded by conservationists and their concerns for retaining, as much as possible, the diversity of natural populations. The need for cryopreservation, thus, is well established."

References 343 20. J. Zel: Micropropagation of Pinus sylvestris 347 1. Introduction 347 2. Micropropagation from embryos 347 3. Micropropagation from seedling explants 350 4. Conclusions 362 5. Summary 362 References 362 21. M. J. Hutzell and D. J. Durzan: Improved aseptic germination and controlled growth for micropropagation of Douglas fir 367 l. Introduction 367 2. Material and methods 367 3. Results and observations 369 4. Discussion 370 5. Summary 372 References 372 22. D. F. Karnosky, Y Huang and D. I. Shin: Micropropagation of Larix species and hybrids 373 1. Introduction 373 2. Micropropagation from juvenile tissues 373 3. Micropropagation from mature trees 376 4. Potential uses of and research needs for micropropagation 377 5. Summary 380 References 380 23. B. J. Nairn: Commercial micropropagation of radiata pine 383 1. Introduction 383 2. Protocols 386 3. Costs 392 4. Future aspects 393 5. Summary 393 References 394 24. P. S. Rao and T. R. Ganapathi: Micropropagation of palms 395 1. Coconut (Cocos nucifera L. ) 395 2. Date palm (Phoenix dactylifera L. ) 400 3. Oil palm (Elaeis guineensis Jacq. ) 405 4. Summary 414 References 415 XI Section III. Tree improvement 423 25. W. J. Libby and M. R. Ahuja: Micropropagation and clonal options in forestry 425 1. Introduction 425 2. Definitions of micropropagation and clonal options 425 3. The selection of genotypes for micropropagation 426 4. The testing of micropropagated clones 427 5. The genetics of clones 429 6. Uses 433 7.

In most breeding programs of plant and animal species, genetic data (such as data from field progeny tests) are used to rank parents and help choose candidates for selection. In general, all selection processes first rank the candidates using some function of the observed data and then choose as the selected portion those candidates with the largest (or smallest) values of that function. To make maximum progress from selection, it is necessary to use a function of the data that results in the candidates being ranked as closely as possible to the true (but always unknown) ranking. Very often the observed data on various candidates are messy and unbalanced and this complicates the process of developing precise and accurate rankings. For example, for any given candidate, there may be data on that candidate and its siblings growing in several field tests of different ages. Also, there may be performance data on siblings, ancestors or other relatives from greenhouse, laboratory or other field tests. In addition, data on different candidates may differ drastically in terms of quality and quantity available and may come from varied relatives. Genetic improvement programs which make most effective use of these varied, messy, unbalanced and ancestral data will maximize progress from all stages of selection. In this regard, there are two analytical techniques, best linear prediction (BLP) and best linear unbiased prediction (BLUP), which are quite well-suited to predicting genetic values from a wide variety of sources, ages, qualities and quantities of data.

The papers in this book were 'in a preliminary version' presented at an international con ference May 21-25, 2002 in Gilleleje, Denmark. It was a joint event, namely the biennial meeting of the Scandinavian Society of Forest Economics and the 3rd Berkeley-KVL Con ference. The Scandinavian Society of Forest Economics (SSFE) was established in 1958 as a forum for forest economists in the Nordic countries to meet and exchange ideas on research and education. Alternating between Denmark, Finland, Norway and Sweden, biennial ordinary meetings have taken place ever since. The number of participants has increased from 10-15 in the first decade to more than 80 in 2002. In the last two decades prominent researchers from outside Scandinavia have been invited to present papers at the biennial meetings and also to participate in ad hoc working groups. The Berkeley-KVL part of the conference is based on a research collaboration between The Royal Veterinary and Agricultural University (KVL), Copenhagen, University of Cali fornia at Berkeley, and Oregon State University. It was initiated in 1993 within the frame work of a research programme at KVL: 'Stochastic Decision Analysis in Forest Manage ment' and since 1996 extended to the programme 'Economic Optimisation of Multiple-Use Forestry and Other Natural Resources'."

It was in late 2002 that the idea of preparing a collection of multi-authored chapters on different aspects of ag- st forestry as a compendium for the 1 World Congress of Agroforestry, June 2004, was tossed around. With the approval of the idea by the Congress Organizing Committee, serious efforts to make it a reality got under way in early 2003. The rigorously peer-reviewed and edited manuscripts were submitted to the publisher in December 2003. Considering the many differentindividualsinvolved in the task as authors and manuscriptreviewers, we feel quite pleased that the task could be accomplished within this timeframe. We are pleased also about the contents on several counts. First of all, the tropical-temperate mix of topics is a rare feature of a publication of this nature. In spite of the scienti?c commonalities between tropical and temperate practices of agroforestry, the differences between them are so enormous that it is often impossible to mesh them together in one publication. Secondly, several of the chapters are on topics that have not been discussed or described much in agroforestryliterature. A third feature is that some of the authors, though well known in their own disciplinary areas, are somewhat new to agroforestry; the perceptions and outlooks of these scholars who are relatively unin?uenced by the past happenings in agroforestry gives a whole new dimension to agroforestry and broadensthescopeofthesubject. Finally, ratherthanjustreviewingandsummarizingpastwork, mostchapterstake the extra effort in attempting to outline the next steps

Much of the world's forested land is dominated by mixed-species stands. Understanding the complex structure and dynamics of these mixtures is a necessary step in the process of formulating appropriate silvicultural systems for their management. David M. Smith, Professor Emeritus of Silviculture at Yale University, has devoted much of his career to the study of the structure, development, and silvicultural treatment of these kinds of stands. This volume is presented by Professor Smith's collegues to honor the contributions he has made to the field. It contains both reviews of past work and results of current studies of mixed stands: topics range from analysis of forest dynamics in unmanaged stands to studies of silvicultural systems applied to mixtures, with examples drawn from boreal, temperate, and tropical regions. Much of the work stresses the importance of understanding the characteristic growth patterns of individual species within mixed stands, and how species interactions shape developmental patterns.

This publication comprises the proceedings of the first International Conference devoted to the structural roots of trees and woody plants. 'The Supporting Roots - Structure and Function, ' 20-24 July 1998, Bordeaux, France. The meeting was held under the auspices ofIUFRO WPS 2. 01. 13 'Root Physiology and Symbiosis, ' and its aim was to bring together scientific researchers, foresters and arboriculturalists, to discuss current problems in structural root research and disseminate knowledge to an audience from a wide disciplinary background. For the first time in an international conference, emphasis was placed on presenting recent reseach in the field of tree anchorage mechanics and root biomechanics. The way in which tree stability can be affected by root system symmetry and architecture was addressed, as well as how movement during wind sway can influence the development and shape of woody roots. The role of different nursery and planting techniques was discussed, in relation to effects on root system form and development. Root response to different environmental stresses, including water, temperature, nutrient and mechanical stress was addressed in detail. The structure and function of woody roots was also considered at different levels, from coarse to fine roots, with several papers discussing the interaction between roots and the rhizosphere. One of the conference highlights was the presentation of new methods in root research, by a series of workshops held at LRBB-INRA, Pierroton, on the northern border of the Gascony forest.