| April 26, 2010 |  |
New UCS Gardening Guide Offers Tips for Climate-Friendly Gardens and Yards
WASHINGTON (April 26, 2010) – Home gardeners can avoid contributing to climate change by using certain techniques and tools that are more climate-friendly than others, according to a new gardening guide released today by the Union of Concerned Scientists (UCS). The science-based guide explains the connection between land use and global warming, and offers recommendations for conscientious gardeners to maximize the amount of heat-trapping carbon dioxide their green spaces store and minimize the other global warming gases gardens can emit.
"Many Americans understand that powering our cars and computers overloads our atmosphere with heat-trapping gases like carbon dioxide," said Karen Perry Stillerman, a senior analyst with the UCS Food and Environment Program. "With the right practices, farmers and gardeners can lock up some of that carbon in the soil."
When too much carbon dioxide and other global warming gases, such as methane and nitrous oxide, are released into the air, they act like a blanket, trapping heat in the atmosphere and altering weather patterns around the world, Stillerman explained. Unchecked climate change will have serious consequences for public health and the environment.
Although agriculture can store carbon and reduce other emissions on a much larger scale, gardeners can help. The Climate-Friendly Gardener: A Guide to Combating Global Warming from the Ground Up (www.ucsusa.org/gardenguide) offers five recommendations for gardeners.
1. Minimize Carbon-Emitting Tools and Products. Gasoline-powered lawn mowers and leaf blowers are obvious sources of heat-trapping carbon dioxide. A typical mower emits 20 pounds of carbon dioxide per gallon. Synthetic fertilizers and pesticides, which require a lot of energy to produce, also contribute to global warming. The new guide provides several tips for avoiding garden chemicals and fossil-fuel-powered equipment.
2. Use cover crops. Bare off-season gardens are vulnerable to erosion, weed infestation and carbon loss. Seeding grasses, cereal grains or legumes in the fall builds up the soil, reduces the need for energy-intensive chemical fertilizers and pesticides, and maximizes carbon storage. The guide recommends that gardeners plant peas, beans, clovers, rye and winter wheat as cover crops and explains the specific advantages that legume and non-legume cover crop choices have for gardens.
3. Plant Trees and Shrubs Strategically. Planting and maintaining one or more trees or large shrubs is an excellent way to remove more heat-trapping carbon dioxide from the atmosphere over a long period of time. A recent study estimated that the trees in U.S. urban areas store nearly 23 million tons of carbon in their tissues every year. That's more than all of the homes, cars, and industries in Los Angeles County emit annually, or about as much as all of the homes in Illinois or Pennsylvania emit every year. Well-placed trees also shade buildings from the summer sun or buffer them from cold winter winds, reducing the need for—and cost of—air conditioning and heating. UCS's guide discusses the most suitable types of trees for a climate-friendly yard.
4. Expand Recycling to the Garden. Yard trimmings and food waste account for nearly 25 percent of U.S. landfill waste, and the methane gas released as the waste breaks down represents 3 to 4 percent of all human-generated heat-trapping gases. Studies indicate that well-managed composted waste has a smaller climate impact than landfills. The UCS guide describes how to create a climate-friendly compost pile.
5. Think Long and Hard about Your Lawn. Residential lawns, parks, golf courses and athletic fields are estimated to cover more than 40 million acres—about as much as all the farmland in Illinois and Indiana combined. A growing body of research suggests that lawns can capture and store significant amounts of carbon dioxide, but some newer studies warn of the potential for well-watered and fertilized lawns to generate heat-trapping nitrous oxide. The science is unsettled, but there are practical things gardeners can do to maximize lawn growth and health with a minimum of fertilizer and water. The new UCS guide summarizes the science and offers tips for homeowners to make their lawns truly "green."
"Gardening practices alone won't solve global warming, but they can move us in the right direction, just like installing super efficient light bulbs and using reusable bags," said Stillerman. "Seventy percent of Americans garden, and they can have a positive impact. Our guide shows them how."
###
The Union of Concerned Scientists puts rigorous, independent science to work to solve our planet's most pressing problems. Joining with citizens across the country, we combine technical analysis and effective advocacy to create innovative, practical solutions for a healthy, safe, and sustainable future.
