Strategically planted conifers can buffer a building from chilly winter winds, and create a dead air space to prevent heat loss. Fuel savings of 20 per cent or more can be realized. The urban forest removes pollutants and other particulates from our air. Each city tree removes about six kilograms of carbon dioxide from the atmosphere each year. Every tree planted contributes to the purification of the air we breathe every day.
Trees also filter air-borne particulates.
But an urban forest's ability to improve air quality is finite. Ultimately, air pollution will damage forest health. Parts of the Black Forest are currently in decline due to air pollution over Germany, while ponderosa pine forests near Los Angeles have suffered significant injury and death due to that city's infamous smog problem. Certain urban trees fulfill functional roles. They are planted as wind and noise barriers for homes or entire neighbouroods, and as soil stabilizers on steep terrain.