London: A new study has recently revealed that manicured lawns are major source of greenhouse gases, which contribute to global warming.
The study confirmed what some environmentalists have long suspected: that the lawn has a bigger problem than rampaging legionaries, the Independent reported.
But the scientists behind the study believe it would still be possible to create a magnificent expanse of green sward if a number of simple steps are taken to reduce its impact on the planet.
Grass lawns soak up carbon dioxide, which is stored in the soil after the cut grass rots and so, like trees, they are considered good for the planet. But Dr Chuanhui Gu of Appalachian State University in the US said that once the energy expended by mowing, fertilizer use and watering are taken into account, lawns actually produce more greenhouse gases than they soak up.
Gu's team developed a maintenance plan that he said typically reduced the emissions by up to 70 per cent, while still producing a pleasant effect. He said mowing should be done about half as frequently, perhaps once a fortnight instead of once a week, with watering kept to a minimum.
And fertilizer, which produces nitrous oxide, a greenhouse gas about 300 times more potent than carbon dioxide and uses a lot of energy to produce, should be used sparingly, ideally only when the grass is newly planted. Instead, grass cuttings should be left on the lawn as a natural alternative.
Mowing less often was a "good idea" and leaving cuttings on the lawn was also sensible, although Guy Barter suggested using a mulching mower that chops up the leaves so they can sink down into the grass.
The study is published in the Journal of Environmental Management.