Greenhouse Lawns of Summer

The lush, green lawns so beloved by U.S. homeowners are contributing to global warming.

• Laura Tangley
• Aug 01, 2006

THOSE LUSH, GREEN LAWNS so beloved by U.S. homeowners are contributing to global warming, say researchers at the U.S. Department of Energy's Oak Ridge National Laboratory. According to the scientists' calculations, applying 137 pounds of fertilizer to an acre of lawn-- the recommended treatment-- generates 405 pounds of carbon dioxide (CO2) and other greenhouse gases. These emissions, which result from production, transportation and application of fertilizers, are equal to the amount of CO2 released by an average family sedan driven about 440 miles. And grass that grows faster also must be mowed more frequently, further increasing CO2 output.

The average U.S. citizen is responsible for nearly 12,000 pounds of CO2 emissions a year. A third comes from power generation, another third from internal combustion-powered vehicles and the rest from other activities. "Energy use is embodied in everything that we use and buy," notes Oak Ridge researcher Gregg Marland. "Just because you may not be burning the fossil fuel yourself, don't kid yourself into thinking that someone isn't burning it on your behalf."