Air pollution in urban areas is a critical environmental concern. Carbon monoxide may reach high concentrations, especially near roadsides. One recent study found that certain turfgrass species are useful because they absorb carbon monoxide.

Turfgrass, shrubs and trees all use carbon dioxide, sunlight and water to produce the nutrients needed for their growth. A by-product of this process is the oxygen we need to live.

A landscape area or yard approximately 40 feet by 50 feet will generate the oxygen required for one person for an entire year. Thus, in a sense, turfgrass, shrubs and trees contribute to the air we breathe.

Turfgrass also reduces the extremely high levels of radiant heat found in urban areas. Urban areas may be 9° to 13° F (5° to 7° C) warmer than nearby rural areas. However, well-maintained turfgrass is considerably cooler than other surfaces. Green, growing turfgrass may be 38° F (21° C) cooler than brown, dormant turfgrass and 70° F (39° C) cooler than a synthetic surface (Table 1).

The cooling effect of green turfgrass and landscapes lowers the amount of energy needed for mechanical cooling of adjacent homes and buildings.

Table 1 Maximum Daytime Temperatures of Four Surfaces

Type of Surface	Maximum Temperature in °F (°C)	Percent Temperature Increase Over Green Turfgrass
Green, growing turfgrass	88°F(31.1°C)	—
Dry, bare soil	102°F(38.9°C)	16%
Brown, dormant turfgrass	126°F(52.2°C)	43%
Synthetic turfgrass	158°F(70.0°C)	80%