January 21, 2010
Another Downside to Your Classic Green Lawn
We should all know by now that lawns of green grass aren’t so “green” for the environment. Keeping turf from turning brown wastes water; people use too much pesticide and herbicide, toxic chemicals that can contaminate the fish we eat and water we drink. And keeping lawns at a reasonable height burns fossil fuels, releasing greenhouse gases and other pollutants into the atmosphere. Now a new study in Geophysical Research Letters shows that turf causes yet another problem, this time from the fertilizer spread to keep grass growing.
Isn't this Arizona xeriscape better than a manicured lawn? (courtesy of Flickr user midwinter)
Two Earth scientists from the University of California, Irvine, sampled two types of turf—ornamental lawn and athletic fields—at four California parks and calculated how much carbon dioxide the grass sequestered and how much nitrous oxide was released through fertilization. (Nitrous oxide is greenhouse gas that is about 300 times more effective than carbon dioxide at trapping heat in our atmosphere.) They also calculated how much carbon dioxide was released through maintenance.
For ornamental lawns that aren’t maintained frequently, such as picnic areas, the turf emits a significant quantity of nitrous oxide, but this was largely offset by the amount of carbon dioxide taken up by the plants. But athletic fields are maintained more closely, and they don’t sequester any carbon. These fields are thus adding to the amount of greenhouse gas in the atmosphere (and I would suggest that anyone obsessed with perfect lawn maintenance could also fit into this category of climate change contributor).
However, that patch of green isn’t necessary; we’ve been growing grass in our yards for less than a century. And there are plenty of alternatives. Xeriscaping (also called xerogardening), for example, uses native plants and mulch to limit the amount of water and maintenance needed in a garden. You could replace the grass with clover, which requires little water and no herbicides and could give you a constant supply of luck. Habitat gardening has the added benefit of attracting wildlife to your space. Or you can plant wildflowers—even replace your concrete driveway. My favorite solution is to replace your lawn with a meadow. Good luck, though, convincing your homeowner’s association on any of these.
Loading ...(Hat tip: Blue Marble)
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When we moved into our new home over two years ago my husband and I decided to tear out the grass and replace it with various plants. We did not do it so much to save the envirnoment but to save the amount of work that goes into keeping a lawn looking “nice”. We have a variety of wildflowers and other plants that are native to central Texas. Month to month the scene varies, but there is usually a lot of color, as well as a variety of butterfiles and bees, as well as occassional hummingbirds.
Our plants stand up the the hot summer weather, the lack of rain that this area has gotten for the last three years, and the occassional freezing temperatures during January nights.
We’ve already replaced most of the grass in our front and back yards with garden plots, ivy on the steep parts, bushes and trees. But we like to keep two grassy areas so we can play croquet. Still, we’ll certainly go with clover. It might slow down the balls quite a bit but, hey!, the best purpose of the game is to relax and get mellow, not to bang your opponent’s ball way off course or to show what a skilled, macho player you are by slamming your own ball thru more than one wicket at a time. Make Play, Not War.
Bruce
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I wonder what the difference between a lawn and a vegetable garden are? Would love to get ahold of these scientists.
I will change my green garden, it is a good idea because the environment will reduce the level of pollution
I understand what is being said, but I really do like the look and feel of green grass.