It is the chief goal of forestry to devise methods for felling trees that provide for the growth of a new forest crop and to ensure that adequate seed of desirable species is shed onto the ground and that conditions are optimal for seed germination and the survival of saplings. The basic rule of timber management is sustained yield; that is, to cut each year a volume of timber no greater than the volume of wood that grew during that year on standing trees.
Desirable timber species are usually those of the native climax vegetation (see ecology) that can perpetuate themselves by natural succession, although at times (intentionally or unintentionally) a forest may not represent the climax vegetation—such as the pine of the SE United States, which grows faster than, and has replaced, the hardwoods destroyed by fire and logging. The Douglas fir of Western forests is encouraged because it is more valuable than the climax vegetation of mixed conifers that tends to establish itself in the absence of human intervention. Planting trees of different sizes (either because of species or of age) prevents crowding and insures maximal growth for the given area. Extermination of diseases and insect pests is standard forestry practice.
The control of forest fires has developed into an independent and complex science costing approximately $100 million annually in the United States. Because of the extremely rapid spreading and customary inaccessibility of fires once started, the chief aim of this work is prevention. However, despite the use of modern techniques (e.g., radio communications, rapid helicopter transport, and new types of chemical firefighting apparatus) more than 10 million acres of forest are still burned annually. Of these fires, about two thirds are started accidentally by people, almost one quarter are of incendiary origin, and more than 10% are due to lightning.
Modern firefighting practice now recognizes that fires caused by lightning are an important tool of nature. Such fires do away with dead underbrush and diseased areas of growth, leaving clear areas for new growth of grass and new generations of trees. Some trees, it has been found, cannot grow without the aid of fire. The cones of the jack pine, for example, need exposure to intense heat to release seed. Other species, such as the Douglas fir and the sequoia, cannot flourish in shaded areas but need the open sunlit space cleared by fire. For such reasons lightning-caused fires in many cases—especially in wilderness areas far from habitation—are now permitted to burn but are carefully monitored and kept under control.
The potential commercial value of the land lost to human-caused fire cannot be calculated: aside from the loss of timber, the damage is inestimable in terms of land rendered useless by ensuing soil erosion, elimination of wildlife cover and forage, and the loss of water reserves collected by a healthy forest. The increasing demand for water to supply growing metropolitan areas and for agricultural irrigation has stimulated the study of the essential role of forests in water conservation.
In 1960 the Forest Service was charged by law with management of the national forests according to a philosophy of sustained yield and multiple use: production of timber, preservation of fish and wildlife habitat, watershed maintenance, mining, grazing, and recreation. In 1964, however, demand for timber led the Forest Service to adopt the practice of clearcutting used also by the commercial timber industry. Vast forest tracts are stripped of all trees, leaving an unsightly bald area. Environmentalists claim that clearcut areas are liable to insect infestation, landslides, and erosion, and that runoff causes siltation of neighboring streams and spoils fish spawning grounds. Environmentalists have also decried the ecologically disruptive effects of strip mining and overgrazing in the national forests and have urged restoration of blighted areas and more equitable multiple-use management in the future. In particular, emphasis has been placed on managing the forests in terms of broad concepts of land use and environmental quality. Like other federal agencies, the Forest Service must now assess the environmental impact of proposed actions, such as building new roads through the forests or granting rights to drill for oil or mine for coal and other minerals (see environmental impact statement; environmentalism).
Forests are vast and valuable expanses; the necessity for government supervision has long been recognized and is today employed virtually throughout the world. The earliest known instance of organized reforestation was in Germany in 1368, and by the mid-18th cent. the practice was well established also in neighboring Austria, Switzerland, and France. German immigrants to the United States (notably Carl Schurz, the first Secretary of the Interior) were instrumental in conserving the new forest lands. After the Timber Culture Act (1873), extensive planting began, although at first mostly in an attempt to forest the plains and prairies. Under President Theodore Roosevelt the first public forests were set aside (see National Forest System). The Civilian Conservation Corps, instituted by President Franklin D. Roosevelt, planted about 2.25 billion trees in the decade from 1933 to 1942, and efforts in forestry have increased significantly in recent years. Today about 27% of U.S. forest is under public ownership, 17% as national forests administered by the Forest Service of the Dept. of Agriculture.
See S. W. Allen, An Introduction to American Forestry (3d ed. 1960); D. M. Smith, The Practice of Silviculture (7th ed. 1962); C. H. Stoddard, Essentials of Forestry Practice (2d ed. 1968).
Foresters may be employed by industry, government agencies, conservation groups, urban parks boards, citizens' associations, or private landowners. Industrial foresters are predominantly involved in planning the timber harvests and forest regeneration. Other foresters have the specific jobs which include a broad array of responsibilities. For example, urban foresters work within city environments to enhance urban trees with their unique needs. Some foresters work in tree nurseries growing seedlings for regeneration projects. Others are involved with tree genetics or developing new building systems as forest engineers. The profession has expanded to include a wide diversity of jobs, typically requiring a college bachelor's degree up to the PhD level for highly specialized areas of work.
Traditionally, professional foresters develop and implement "forest management plans". These plans rely on tree inventories showing an area's topographical features as well as its distribution of trees (by species) and other plant cover. They also include roads, culverts, proximity to human habitation, hydrological conditions, and soil reports ecological sensitive areas. Finally, forest management plans include the projected use of the land and a timetable for that use.
Plans for harvest and subsequent site treatment are influenced by the objectives of the land's owner or leaseholder (for instance, a timber company that holds cutting rights to a given tract of land, or the government in the case of state-owned forests). There is an increasing trend to consider the needs of other stakeholders (e.g., nearby communities or neighborhoods, or rural residents living within or adjacent to the forest tract). Plans are developed with the prevailing forest harvest laws and regulations in mind. They ultimately result in a prescription for the harvest of trees, and indicate whether road building or other forest engineering operations are required.
Traditional forest management plans are chiefly aimed at providing logs as raw material for timber, veneer, plywood, paper, wood fuel or other industries. Hence, considerations of product quality and quantity, employment, and profit have been of central, though not always exclusive, importance.
Foresters also frequently develop post-harvest site plans. These may call for reforestation (tree planting by species), weed control, fertilization, or the spacing of young trees (thinning of trees that are crowding one another).
While other duties of foresters may include preventing and combatting insect infestation, disease, forest and grassland fires, there is an increasing movement towards allowing these natural aspects of forest ecosystems to run their course, where possible, usually excepting epidemics or risk of life or property. Foresters are specialists in measuring and modelling the growth of forests (forest mensuration). Increasingly, foresters may be involved in wildlife conservation planning and watershed protection.
The use and management of forest resources has a long history in China, dating from the Han Dynasty and taking place under the landowning gentry. It was also later written of by the Ming Dynasty Chinese scholar Xu Guangqi (1562-1633). In the Western world, formal forestry practices developed during the Middle Ages, when land was largely under the control of kings and barons. Control of the land included hunting rights, and though peasants in many places were permitted to gather firewood and building timber and to graze animals, hunting rights were retained by the members of the nobility. Systematic management of forests for a sustainable yield of timber is said to have begun in the 16th century in both the German states and Japan. Typically, a forest was divided into specific sections and mapped; the harvest of timber was planned with an eye to regeneration.
The practice of establishing tree plantations was promoted by John Evelyn; it had already acquired some popularity in the British Isles. Schools of forestry were established after 1825; most of these schools were in Germany and France. During the nineteenth and early twentieth centuries, forest preservation programs were established in the United States, Europe, and British India. Many foresters were either from continental Europe (like Sir Dietrich Brandis), or educated there (like Gifford Pinchot).
The enactment and evolution of forestry laws and binding regulations occurred in most Western nations in the 20th century in response to growing conservation concerns and the increasing technological capacity of logging companies.
Tropical forestry is a separate branch of forestry which deals mainly with equatorial forests that yield woods such as teak and mahogany. Sir Dietrich Brandis is considered the father of tropical forestry.
Today a strong body of research exists regarding the management of forest ecosystems, selection of species and varieties, and tree breeding. Forestry also includes the development of better methods for the planting, protecting, thinning, controlled burning, felling, extracting, and processing of timber. One of the applications of modern forestry is reforestation, in which trees are planted and tended in a given area.
In many regions the forest industry is of major ecological, economic, and social importance. Third-party certification systems that provide independent verification of sound forest stewardship and sustainable forestry have become commonplace in many areas since the 1990s. These certification systems were developed as a response to criticism of some forestry practices, particularly deforestation in less developed regions along with concerns over resource management in the developed world. Some certification systems are criticised for primarily acting as marketing tools and lacking in their claimed independence.
In topographically severe forested terrain, proper forestry is important for the prevention or minimization of serious soil erosion or even landsliding. In areas with a high potential for landsliding, good forestry can act to prevent property damage or loss, human injury, or loss of life.
Public perception of forest management has become controversial, with growing public concern over perceived mismanagement of the forest and increasing demands that forest land be managed for uses other than pure timber production, for example, indigenous rights, recreation, watershed protection and preservation of wilderness and wildlife habitat. Sharp disagreements over the role of forest fires, logging, motorized recreation and others drives debate while the public demand for wood products continues to increase.
The first dedicated forestry school was established by Georg Hartig at Dillenburg in Germany in 1787, though forestry had been taught much earlier in central Europe. The first in North America was established near Asheville, North Carolina, by George Vanderbilt after he saw the devastation logging had caused in the area. The grounds of his Biltmore Estate are almost entirely managed forest, which has grown from bare ground to mature trees since 1895. Another early school was the New York State College of Forestry at Cornell established in 1898. Early North American foresters went to Germany from the nineteenth century to study forestry. Some early German foresters also emigrated to North America.
Today, an acceptably trained forester must be educated in general biology, botany, genetics, soil science, climatology, hydrology, economics and forest management. Education in the basics of sociology and political science is often considered an advantage.
An interesting scope of work opens up for foresters interested in international politics. Organizations such as the Forest Policy Education Network (FPEN) are dedicated to facilitate the way into forest politics and to exchange information on the subject.
In India the Forestry Education is imparted in the Agricultural Universities and In Forest Research Institute (Deemed University), Dehradun.Dr.Y.S.Parmar University of Horticulture and Forestry, Solan (HP) is dedicated for imparting the Forestry education and is the only University of its kind in Asia. Four year Degree programme is conducted in these universities at Undergraduate level. Post Graduation and Doctorate degree facility is also available in these universities
Tropic Ventures Rainforest Enrichment and Sustainable Forestry Project is registered under the Auxiliary Forest Program of Puerto Rico, and is a demonstration project for students and foresters interested in the sustainable management and preservation of tropical rainforest land.