Woody vegetation has been found to reduce carbon monoxide. Halogens, both chlorine and fluorine, are reduced by woody vegetation, with chlorine being removed at a much higher rate. Halogens are damaging to many plant species. Plants will absorb and use ammonia for its nitrogen content. Trees remove ozone from the air at a rapid rate.
Ozone can damage foliage on many types of trees.
Trees can help reduce the greenhouse effect in two ways. Second, shade from trees can reduce air conditioning energy use, which reduces the amount of CO 2 emitted by power plants. These surfaces allow rainwater to flow across them, picking up pollutants that are on the surface in the process. Leaves and bark from trees catch the rain and reduce its impact on the ground. In addition, the roots slow the movement of water through the soil, thus reducing soil erosion so that less pollution is flushed into rivers, streams, and wetland areas.