Preface Forest provides habitats for animals and livelihoods for humans. Forest can influence weather patterns. Forest supplies wood, food and fodder, and contributes indirectly to household food security, through the generation of employment and income from the sale of forest products. So the forest is a valuable ingredient in the economic and social fabrics of a country. The importance of forest is now being realized in the backdrop of climate change loss of biodiversity, and ecological and environmental imbalance. Thus throughout the world, forestry is gaining importance as a subject of general interest and many universities have recommended it as a core subject in their curricula. Keeping this in view, this textbook Introduction to Forestry has been written for the undergraduate students of agriculture as per the latest ICAR syllabus. The book has been divided into eight chapters covering major aspects of forestry including definitions of basic terms related to forestry, forest classification, Indian forest policies, forest regeneration, tending operations forest mensuration, agroforestry and cultivation practices of some multipurpose tree species. Any suggestion to improve the contents of the book will be highly appreciated. I take full responsibility for any errors in this book. Any shortcomings may be intimated so that it will be taken care of. Originality of the contents in this book is not claimed. In writing this book,a number of books, periodicals and journals have been referred. I extend my sincere thanks to the authors and editors of these books and journals. Every care has been taken to cite the bibliographic references. However, any omissions, misrepresentations, incorrect citations or other mistakes that may have occurred are regretted. I am grateful to my colleagues in the All India Coordinated Research Project on Integrated Farming Systems, Odisha University of Agriculture & Technology, Bhubaneswar for their help in various ways during the preparation of this textbook.

A forest is a large area dominated by trees. Many definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing and ecological function. Although a forest is usually defined by the presence of trees, under many definitions an area completely lacking trees may still be considered a forest if it grew trees in the past, will grow trees in the future, or was legally designated as a forest regardless of vegetation type. According to the Food and Agriculture Organization, forests covered 4 billion hectares or approximately 30% of the world’s land area in 2006. Forests are the dominant terrestrial ecosystem of earth, and are distributed around the globe. Forests account for 75% of the gross primary production of the earth’s biosphere, and contain 80% of the earth’s plant biomass. DEVELOPMENT OF MODERN FORESTRY Systematic management of forests for a sustainable yield of timber began in Portugal in the 13th century when Afonso III, the king of Portugal planted the trees to prevent coastal erosion and soil degradation, and as a sustainable source for timber used in naval construction. His successor Dom Dinis continued the practice and the forest exists still today. Forest management also started in German in the 14th century and in Japan in the 16th century. The practice of establishing tree plantations in the British Isles was promoted by John Evelyn during second half of the 17th century. During the late 19th and early 20th centuries, forest preservation programmes were established in British India, the United States, and Europe. Sir Dietrich Brandis is considered the father of tropical forestry. He brought European concepts and practices to the tropical and semi arid climate zones. The enactment and evolution of forest laws and binding regulations occurred in most Western nations in the 20th century in response to growing conservation concerns. Tropical forestry is a separate branch of forestry which deals mainly with equatorial forests that yield woods such as teak and mahogany. One of the applications of modern forestry is reforestation, in which trees are planted and tended in a given area.

The Indian ancient texts have some mention of the forest and the activities that were performed in the forests. Forests were revered by the people and a large number of religious ceremonies centred on trees and plants. Ancient Hindu culture is said to have evolved in the forest. The epics Ramayana and Mahabharata give an attractive description of forests. The Agni Purana, written about 4000 years ago, stated that man should protect trees to have material gains and religious blessings. Around 2500 years ago, Gautama Buddha preached to his followers to plant trees. There is enough evidence to show that dense forests once covered India. But the growing population and man’s dependence on the forest for infrastructural developments caused the depletion of forests. HISTORY OF INDIAN FORESTS The earliest indication of forestry administration in India is found in 300 BC. It was during the reign of Chandragupta Maurya. He realized the importance of the forests and appointed a Superintendent of Forests who looked after forests and wildlife. Later Ashoka continued the process. He launched programmes to plant trees on a large scale. Much importance was also given for planting trees along roadsides and temple premises. These rules continued even during the Gupta period.

The process of replacing the existing mature forest with a new generation of the forest trees is called forest regeneration. It can also be defined as process by which new tree seedlings become established after forest trees have been harvested or have died from fire, insects, or diseases. Forest regeneration is one of the basic tasks of foresters. Regeneration plays such a prominent role in silviculture that most silvicultural systems are named for their method of regeneration.

Silviculture is the branch of forestry dealing with the establishment, development, care and reproduction of trees. Forestry is anything done in the forest and silviculture is anything done to forests. ‘Silva’ is the Latin word for forest and ‘culture’ for cultivation. Silviculture is narrower than forestry, being concerned only with forest plants, but is often used synonymously with forestry. The Society of American Foresters defines silviculture as theory and practice of establishment, composition, constitution and growth of forests. Thus, silviculture refers to art and science of raising forest crops, methods of raising tree crops, their growth and aftercare up to the time of final harvesting. In simple words, silviculture is the growing and tending stands of trees. Silviculture is also used to manage forests for wildlife, water, recreation, aesthetics, or any combination of these or other forest uses.

Tending is the term applied to pre-harvest silvicultural treatment of forest tree crops at any stage after initial planting or seeding. In other words, tending is the intermediate treatments that forest vegetation receives after establishment of regeneration and prior to final harvest of the stand. These tending operations can occur throughout the life of the forest stand, but do not include efforts directed at establishing regeneration. Tending operations play a fundamental role in the improvement of quality and stability of forest stands. Tending the trees after planting creates favourable conditions for both the plants’ survival and to stimulate a healthy, vigorous growth. Tending operations keep the plants from being suppressed by natural vegetation. It essentially covers operation on the crop itself and competing vegetation. Weeding, cleaning and thinning are important tending operations. Even improvement felling comes under tending operations but regeneration felling is not a tending operation. The major objectives of tending are to maintain sanitation, provide sufficient growing space, and more light, water, nutrients, etc. to the tree crops.

Mensuration is derived from Latin word mensura which means measure. It means measurement of length, mass, time, etc. It is an art and science of locating, measuring and calculating the length of lines, areas of planes, and volumes of solids. Forest mensuration is one of the most fundamental disciplines within forest and related sciences. It concentrates on trees and forests or potentially forested locations and deals with the measurement of trees and stands and the analysis of the resultant information. Forest mensuration also includes measuring or calculating growth and change in trees and forests. Forest mensuration thus may be defined as the art and science of providing the quantitative information about trees and forest stands necessary for forest management, planning and research. Chaturvedi and Khanna (1986) defined forest mensuration as a branch of forestry which deals with the determination of dimensions (diameter, height, volume, etc.), form, age and increment of single trees, stands or whole woods, either standing or after felling. According to the Society of American Foresters, forest mensuration is the determination of dimensions, form, weight, growth, and age of trees individually or collectively, and of the dimensions of their products (Helms, 1998). It is a tool that provides facts about the forest crops or individual trees to sellers, buyers, planners, managers and researchers. Forest mensuration provides quantitative information regarding forest resources that will allow making reasonable decisions on its density, use and management. Forest mensuration serves the following objects

Agroforestry is a new name for a set of old practices. The farmers have been practicing agroforestry since ancient times. The general concept of agroforestry is to integrate trees and agriculture so as to create a more diversified landscape, while providing the producers with new environmental and economic benefits. In other words, agroforestry is a method of farming that allows trees and shrubs to grow along with crops and/or livestock, therefore blending agriculture and forestry in the same production system. This relatively young science was brought from the realm of indigenous knowledge into the forefront of agricultural research four decades ago and was promoted widely as a sustainability-enhancing practice that combines the best attributes of both forestry and agriculture.

Multipurpose trees and shrubs are defined as all woody perennials that are purposefully grown to provide more than one significant contribution to the production and/or service functions of a land-use system that they occupy. In agroforestry systems, different species of trees and shrubs can be planted with many types of crops in a variety of patterns. Thus, it is required to know about the methods of propagation and nursery raising, planting and other silvicultural management practices along with the diverse uses of multipurpose trees and shrubs of tropical and subtropical areas before their selection for forestry and agroforestry activities. It is important to select the most suitable tree species since it is not easy to replace them once they have been planted. MANGIUM (Acacia mangium) Acacia mangium is a single-stemmed evergreen tree that grows to 25-35 m in height and up to 60 cm in diameter. The bole is usually straight, often fluted near the base, free of branches for up to half its height. Mangium is native to Australia, Indonesia and Papua New Guinea. However, it tolerates varied site conditions and has adaptability to different planting objectives. Mangium shows most vigorous growth on well-drained, fertile soils in high rainfall areas in the humid tropics. It is valued for its rapid growth and has been planted throughout the humid tropics and is a major plantation species in the Asia-Pacific. Provenances from Papua New Guinea consistently show better growth in height and diameter.

Selected References Agrawala, V. P. 1985. Forests in India, Environmental and Production Frontiers. Oxford & IBH Publishing Co., New Delhi. Avery, T. E., Burkhart, H. E. 2002. Forest Measurements. McGraw-Hill, New York. Balooni, K. and Singh, K. 2007. Prospects and problems of afforestation of wastelands in India: A synthesis of macro- and micro-perspectives’. Geoforum 38(6): 1276-1289. Bandopadhyay.1997. A Text Book of Agroforestry with Application. Vikash Publishing House Pvt. Ltd., New Delhi. Bene, J. G., Beall, H. W. and Cote, A. 1977. Trees, food and people: Land management in the tropics. IDRC, Ottawa, Canada. Blakeney, B. 2013. Hand Book of Forestry. Agrotech Press, New Delhi. Carron, L. T. 1968. An Outline of Forest Mensuration. Australian National University Press, Canberra, Australia. Champion, H. G. and Seth, S. K. 1968. A Revised Survey of Forest Types of India, Govt. of India Press, New Delhi, p. 404. Champion, H. G. and Seth, S. K. 1968. General Silviculture for India. Publication Branch, Govt. of India, Delhi. Chaturvedi, A. N. and Khanna, L. S. 2011. Forest Mensuration. International Book Distributers, Dehradun.