TurfMutt

Turfgrass can boost your oxygen footprint.

Compared to bare ground, non-green areas, and lawn substitutes, such as painted concrete or even artificial turf, actual grass and green areas generate oxygen. For example, a turf area 50′ x 50′ produces enough oxygen to meet the everyday needs of a family of four and each acre of grass produces enough oxygen for 64 people a day.
(Source: http://www.turfgrasssod.org)