Afforestation is the opposite of deforestation. In order to reduce global warming and to make sure trees are not wasted, some man-made forests are built, to ensure that cut down trees are replaced. However, if the wrong trees are planted in the wrong places, it defeats the purpose entirely. It is better than deforestation as deforestation causes a tremendous loss of trees.
The idea of afforestation is to increase forestry in certain areas, and to also reduce the amount of carbon in the atmosphere. Trees and plants photosynthesize by taking in carbon dioxide and 'breathing out' oxygen. Oxygen is the most useful gas to man.
To make plantation easier and faster, foresters use tools, such as tree planting bars.