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Deptt. of Agronomy Bihar Agriculture University, Sabour, Bhagalpur, Bihar-813210 Introduction to Forestry (2=1+1) Theory

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Deptt. of Agronomy Bihar Agriculture University, Sabour, Bhagalpur, Bihar-813210 Introduction to Forestry (2=1+1) Theory Teaching Material on AAG 112 Introduction to Forestry (2=1+1) Compiled by: Dr. Shashank Tyagi Asstt. Professor cum Junior Scientist & Pravesh Kumar Asstt. Professor cum Junior Scientist Deptt. of Agronomy Bihar Agriculture University, Sabour, Bhagalpur, Bihar-813210 Introduction to Forestry (2=1+1) Theory: S.N. Particulars No. of Lectures 1. Introduction – definitions of basic terms related to forestry, objectives of 1 silviculture, forest classification, salient features of Indian Forest Policies. 2. Forest regeneration, Natural regeneration - natural regeneration from seed 2 and vegetative parts, coppicing, pollarding, root suckers. 3. Artificial regeneration – objectives, choice between natural and artificial 2 regeneration, essential preliminary considerations. 4. Crown classification. Tending operations – weeding, cleaning, thinning – 1 mechanical, ordinary, crown and advance thinning. 5. Forest mensuration – objectives, diameter measurement, instruments used 1 in diameter measurement. 6. Non instrumental methods of height measurement - shadow and single pole 2 method; Instrumental methods of height measurement - geometric and trigonometric principles, instruments used in height measurement. 7. Tree stem form, form factor, form quotient, measurement of volume of 2 felled and standing trees, age determination of trees. 8. Agroforestry – definitions, importance, criteria of selection of trees in 1 agroforestry, different agroforestry systems prevalent in the country, 9. Shifting cultivation, Taungya. 2 10. Alley cropping. 1 11. Wind breaks and shelter belts, home gardens. 1 12. Cultivation practices of two important fast growing tree species of the 2 region. Total 18 Practical: 1. Identification of tree-species. 3 2. Diameter measurements using calipers and tape, diameter measurements of 2 forked, buttressed, fluted and leaning trees. 3. Height measurement of standing trees by shadow method, single pole 2 method and hypsometer. 4. Volume measurement of logs using various formulae. 3 5. Nursery lay out, seed sowing, vegetative propagation techniques. 3 6. Forest plantations and their management. 3 7. Visits of nearby forest based industries. 2 Total 18 Chapter 1 Introduction – definitions of basic terms related to forestry, objectives of silviculture, forest classification, salient features of Indian Forest Policies. INTRODUCTION: Forestry is nature‘s greatest bounty to mankind. With the depletion and degradation of natural resources by over use we are still lagging far behind in the process of development through modernization. Availability of resources is generally much below the world average and far below the average of developed countries. The country do not have enough land space and the productivity of the available space as far as the forests are concerned is also very low. Forests in India cover about 22.8 %. Estimates of the area currently classified as forest land in India vary widely from as high as 75 million hectares to as low as less than 40 million hectares. This represents 23 and 12 per cent respectively total land area of the country (327.7 M.ha) of the total geographical area admeasuring 74.72 m.ha as against 33 1/3 % enunciated in the National forest policy 1988 to maintain the ecological balance of forest area in A.P. is 6.3 m.ha covering 23.2 % of the total geographical area (27.7 m.ha). as compared to the world average of 1.6 ha per capita forest area, India has 0.11 ha per capita forest area mainly due to the population increase. The country has lost about 43.4 m.ha of forest area during 1951-52 to 1982 – 83 @ 1.5 m.ha / annum, the main reasons being excessive biotic interference, removal of cut forest exceeding than the forests could produce, diversion of area for agriculture for river valley projects and industries etc. The productivity of Indian forest is also very low 0.5 m/ha when compared to the world average of 2 m/ha because of over exploitation, overgrazing and excess maltreatment of forest area in the past. In India most of the forests (95%) are owned and managed by the government in contrast to the management of forests by private sector in the European countries. Although forests occupy 22.8 % they are reported to contribute not much (1%) towards the national economy when compared to agriculture (35%), many reasons have been attributed to the low revenue. Removal of large amount of forest produce by the local population in the form of rights and concessions as well as illicit removals being the main ones. Yet another problem faced by the Indian forestry is the lack of proper investment in reforestation and afforestation programmes. (the investments never exceeded 0.75% of the total plan outlay in the public sector). During the five year plans large scale development and rehabilitation works were launched in the forestry. With the introduction of conservation and forest management the work of demarcation of forest areas and working plan preparation was taken up. At present as a consequence the area covered under working plans constitutes about 66 % of total forest area. Definitions of basic terms related to forestry: Adaptive Management A type of forest land management in which, as an ongoing process, the monitoring of results of management decisions, in relation to sustaining ecosystem characteristics and changes in societal goals, is used to modify management approach. Advance Regeneration (Reproduction) syn. Advance Growth Seedlings or saplings that develop or are present in the understory. Afforestation: Establishing a forest by artificial means on an area on which not forest vegetation has existed for a long time in the past. Age Class (Cohort) A distinct aggregation of trees originating from a single natural event or regeneration activity, or a grouping of trees, e.g., 10-year age class, as used in inventory or management. Age classification: The division of a crop according to difference in age or the allotment of woods to age classes. Age crop: The age of a regular crop corresponding to its crop diameters. Agroforestry : Deals with the integration of crops, forest plants or livestock Alpine: Zone of vegetation where winter is server, slow fall heavy, the mean annual temperature is 450F and the mean January temperature below 300F. In India Himalayan at the altitude above 10,000 ft. and behavior of the soil upon which forest is to be established and behaviour of wood under varying conditions. Artificial Regeneration (Reproduction) An age class created by direct seeding or by planting seedlings or cuttings. Basal area: The area of the cross section of a stem at breast height, when applied to a crop, the sum of basal areas of all the stems or the total basal areas per unit area. Biological Diversity The variety and abundance of life forms, processes, functions, and structures including the relative complexity of species, communities, gene pools, and ecosystems at spatial scales that range from local through regional to global (syn. Biodiversity). Bole: The main stem of a tree. Breast height: Almost universally adopted as the standard height for measuring the girth, diameter and a basal areas of standing trees. India 4‘6‖ (1.37m). In U.K. and most commonwealth countries 4‘.3‖ (1.30m) Canopy The foliar cover in a forest stand consisting of one or several layers. Cleaning A release treatment made in an age class not past the sapling stage in order to free the favored trees from less desirable individuals of the same age class that overtop them or are likely to do so (see Improvement Cutting, Liberating, Weeding). Clearcutting with Reserves A clearcutting method in which varying numbers of reserve trees are not harvested to attain goals other than regeneration. Clearcutting A method of regenerating an even-aged stand in which a new age class develops in a fully exposed microclimate after removal, in a single cubing, of all trees in the previous stand. Regeneration is from natural seeding, direct seeding, planted seedlings, and/or advance reproduction. Cutting may be done in groups or patches (Group or Patch Clearcutting), or in strips (Strip Clearcutting). In the Clearcutting System, the management unit or stand in which regeneration, growth, and yield are regulated consists of the individual clearcut stand (see Group Selection). When the primary source of regeneration is advance reproduction, the preferred term is Overstory Removal. Codominant Trees with crowns forming the general level of the main canopy in even-aged stands or, in uneven-aged stands, the main canopy of the tree's immediate neighbors, receiving full light from above and comparatively little from the sides. Composition, Stand The proportion of each tree species in a stand expressed as a percentage of either the total number, basal area, or volume of all tree species in the stand. conversion and putting the forest produce for a variety of uses like timber, fuel, Coppice Methods Methods of regenerating a stand in which the majority of regeneration is from stump sprouts or root suckers. Coppice with Reserves A coppice method in which reserve trees are retained to attain goals other than regeneration. The method normally creates a two-aged stand. Coppice: When certain plants or seedling are cut from near ground level, they produce a flush of fresh shoots. This is known as coppicing Coupe: A felling area, usually one of an annual series unless otherwise stated. Preferable numbered with Roman numbers as, I, II, III etc. Crop Tree Any tree that is selected to become a component of a future commercial harvest. Crown Class A class of tree based on crown position relative to the crowns of adjacent trees. Crown Cover The ground area covered by the crowns of trees or woody vegetation as delimited by the vertical projection of crown perimeters and commonly expressed as a percent of total ground area (syn. Canopy Cover). Crown Density The amount and compactness of foliage of the crowns of trees and/or shrubs.
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