Americans like manicured green lawns. How do we know? There are more than 25 million acres (10 million hectares) of lawn in the United States, roughly the size of Pennsylvania, Delaware and Rhode Island combined, and every year, homeowners spend more than $6 billion to keep those lawns looking tip-top [source: The Lawn Institute].
Keeping them green, mowed and maintained is good for more than aesthetics -- turfgrasses are good for the environment because they release oxygen while trapping dust, dirt and polluting gasses such as carbon dioxide, hydrogen fluoride and perosyacetyle nitrate. They're also responsible for water filtration, and they help reduce erosion and runoff.
So what can be done when drought conditions try to ruin our lawns? Keeping grass green has more to do with how it's maintained before the drought hits than how often it's watered during lean times. Lawns are able to survive long periods without water -- often they will turn brown and go dormant, but after the drought lifts, they'll bounce back in a few weeks.
The good news is that there are steps you can take before the brown sets in, including making small changes to the way you mow. By raising the lawn mower blade, you'll remove only the top third of each blade and keep the grass tall (at about 3 inches or 7 centimeters). This gives the roots increased shade and more shade means less evaporation. Mulching also helps a lawn retain moisture; the simplest way to mulch is to leave grass clippings on the lawn after mowing.
Although it's a good place to start, keeping grass green during a drought takes more than adjusting how you mow. While some people try laying down imitation turf or applying green paint, we've got more holistic suggestions like xeriscaping and rain barrels, next.