eChapters

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.

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.

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

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.

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.

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.

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.

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.

Abstract: The Santhals of Orissa raise Teak (Tectona grandis) and Cashew nut(Anacardium occidentale) on their marginal and wastelands randomly to meet their contingencies. Upland is utilized for short duration upland paddy cultivation for food. The sporadically grown Teak and Cashew is used as insurance crops for meeting the high risk of dry land paddy. This work is unique and innovative as it was carried out in participatory mode on the pooled land from 14 Santhal households.  It is a maiden attempt in Orissa to develop Agroforestry models using forestry (teak) and horticulture (cashewnut) interventions into the paddy cultivation on uplands by Santhals without much alteration in their age old traditional agricultural practice. The basic objective of this research is to develop most profitable Agroforestry system(s) to provide best land use option for the risk prone dry land paddy cultivation to improve the farmers’ economy with simultaneous natural resource conservation.
 
The Agroforestry models Silvi-horticulture (Teak and Cashewnut)  Agri-silviculture (Paddy and Teak), Agri-horticulture (Paddy and Cashewnut) and Agri-silvi-horticulture (Teak, Cashew nut and Paddy) were developed by the Santhal tribe in Mayurbhanj District of Orissa. The inputs and planting material were sponsored by a leading NGO- Gamin Vikas Trust, which is working on poverty alleviation through Natural Resource Management of the State.

Introduction

Bamboos are group of woody perennial evergreen plants in the true grass family Poaceae, subfamily Bambusoideae, tribe Bambuseae. Bamboos are the fastest growing woody plants (up to 60 centimeter/day) in the world. Bamboo cultivation, especially in intensively managed and productive plantation has attracted a great interest in recent years leading to huge demand of good quality planting material. The easiest and most common method for propagation is seeds. However, in bamboo due to a long flowering cycles, seeds are not available every year and being a cross-pollinating species seedling population show much variability in characters. Species like Bambusa vulgaris and Bambusa balcooa flowers rarely and do not produce seeds making propagation absolutely dependent on vegetative means. Vegetative propagation offers a tremendous scope for mass multiplication of many commercially important species. Bamboos are vegetatively propagated through clump divisions, rhizomes, offsets, layering, marcotting, culm cutting, branch cutting, macroproliferation and through in vitro techniques. Propagation through clump divisions, rhizomes and offsets yield limited number of plants. Layering and marcotting techniques are not fit for commercial production. In vitro methods offer great scope for mass multiplication, but require high initial cost and skilled manpower and thus are not viable for decentralized forest nurseries.

Introduction
 
Historically, foresters did not view trees as typical plants having the systems of heredity similar to all other living organisms. Previously it was felt that the tree development depended only upon the environment in which it was grown. Recently, the “forest tree parentage” in the tree improvement programme has gained importance.  Although there are several breeding methods for improvement of any crop, the most commonly used breeding method in tree improvement is “selection” of superior trees from existing or established population. The objective of selection programme is to obtain significant amount of genetic gain as quickly and inexpensively as possible, while at the same time maintaining a broad genetic base to ensure the future genetic general principle; that is choosing the most desirable individuals for the use as parent in breeding and production programmes.

The most successful tree improvement programmes are those in which proper vegetative propagules and provenances are used. Success in the establishment and productivity of forest plantations is determined largely by the species used and the source of seed or vegetative propagules used within the population.

Abstract: This article gives an overview of the possibility and scope of successful cultivation of medicinal and aromatic herbs as intercrops with multipurpose tree species under agroforestry conditions. The challenges are many. Sustainable production under any agroforestry system is the main goal to be achieved through short and long term strategies. Diversification of the existing conventional cropping sequences coupled with developing of suitable technology packages is the need of the hour to cope up with ever increasing demand for diversified products. The hypothesis is, if intercropping of annuals, biennials and perennial medicinal plants in association with fuel, fodder, timber, pulp, fruit trees including tree species with medicinal values on the farmland, an alternate land use system; can provide economically viable option for sustainable systems. This chapter describes the potential and benefits of medicinal plants based agroforestry. Our experience is that planting timber, fuel and fodder or fruit tree species in combination with medicinal crops paves the way for diversified products and better economic returns to the farmers. Multipurpose tree species outside the forest have played very important role in catering to the day to day requirements of the rural population. Different farming systems consisting of crops + trees have yielded encouraging results and have not only helped diversification but enhanced productivity of land per unit area. Intercropping medicinal and aromatic herb species further makes agroforestry more remunerative.

Introduction

Dry lands cover nearly one-third of the earth’s total surface and characterized by high climatic variability in rainfall and temperature along with higher potential of wind and water erosion (Mainguet, 1991; Okin, 2000). Wind erosion has been identified as one of the overriding factors of desertification in regions characterized by strong and persistent winds through out an annual dry season (Le Houerou, 1996). Clear sweep of strong winds across sandy desert is the great hindrance in sustenance and progress of agricultural activities. The strong blowing winds on one hands takes away top fertile soil thus causing irreparable loss to soil productivity, on the other hand deposition of airborne soil particles (sand, silt and clay) block the roads, railways, water bodies, open canals and burry agricultural fields (Gupta and Aggrawal,1978; Prasad et al, 2004). To minimize erosion hazards of speedy winds and optimize production of agricultural crops, various efforts have been made in the past by adopting different soil conservation measures among which the windbreak/ shelterbelt plantations rank high due to their expected effects on wind velocity, microclimate and productivity.