Agroforestry is an integration of trees, crops and livestock on the same plot of land. The main objective is on the interaction among them . Example: intercropping of two or more crops between different species of trees and shrubs, which results in higher yielding and reducing the operation costs. This intentional combination of agriculture and forestry has varied benefits including increased bio-diversity and reduced erosion.
Some of the major species cultivated in commercial Agroforestry include Casuarina, Eucalyptus, Malai Vembu, Teak and Kadambu trees which were among the 20 species identified as commercial timber. They are of great importance to wood-based industries.
Benefits of agroforestry
• It is an answer to the problem of soil and water conservation and also to stabilise the soil (salinity and water table) reduce landslide and water run-off problem.
• Nutrient cycling between species improves and organic matter is maintained.
• Trees provide micro climate for crops and maintain O2 – CO2 balanced, atmospheric temperature and relative humidity.
• Suitable for dry land where rainfall is minimum and hence it is a good system for alternate land use pattern.
• Multipurpose tree varieties like Acacia are used for wood pulp, tanning, paper and f irewood industries.
• Agro-forestry is recommended for the following purposes. It can be used as Farm Forestry for the extension of forests, mixed forestry, shelter belts and linear strip plantation.
Rehabilitation of degraded forests and recreation forestry
The production of woody plants combined with pasture is referred to silvopasture system. The trees and shrubs may be used primarily to produce fodder for livestock or they may be grown for timber, fuel wood and fruit or to improve the soil. T his system is classified into following categories.
i. Protein Bank:
In this various multipurpose trees are planted in and around farm lands and range lands mainly for fodder production. Example: Acacia nilotica, Albizzia lebbek, Azadirachta indica, Gliricidia sepium, Sesbania grandiflora.
ii. Livefence of fodder trees and hedges:
Various fodder trees and hedges are planted as live fence to protect the property from stray animals or other biotic influences. Example: Gliricidia sepium, Sesbania grandiflora, Erythrina spp., Acacia spp..
It refers to the sustainable management of forests by local communities with a goal of climate carbon sequestration, change mitigation, depollution, deforestation, forest restoration and providing indirect employment opportunity for the youth. Social forestry refers to the management of forests and afforestation on barren lands with the purpose of helping the environmental, social and rural development and benefits. Forestry programme is done for the benefit of people and participation of the people.
Trees grown outside forests by government and public organisation reduce the pressure on forests. In order to encourage tree cultivation outside forests, Tree cultivation in Private Lands was implemented in the state from 2007-08 to 201112. It was implemented by carrying out block planting and inter-crop planting with profitable tree species like Teak, Casuarina, Ailanthus, Silver Oak, etc. in the farming lands and by a free supply of profitable tree species for planting in the bunds. The Tank foreshore plantations have been a major source of firewood in Tamil Nadu. The 32 Forestry extension centres provide technical support for tree growing in rural areas in Tamil Nadu. These centres provide quality tree seedlings like thorn / thornless bamboo, casuarinas, teak, neem, Melia dubia, grafted tamarind and nelli, etc. in private lands and creating awareness among students by training / camps.
Major activities of forestry extension centres
• Training on tree growing methods
• Publicity and propaganda regarding tree growing
• Formation of demonstration plots
• Raising and supply of seedlings on subsidy
• Awareness creation among school children and youth about the importance of forests through training and camps.