• Wrapping paper—usually made from virgin materials—is a large part of the holiday-waste stream. And if it's shiny or sparkly, it can't even be recycled. If every household wrapped three gifts in recycled materials (reused maps or cloth make great trimmings), we'd save reams and reams of paper. (Here's one calculation.) Other alternatives include buying gift-wrap made from recycled paper or hemp and flax. While you're at it, try Sellotape, which is made from biodegradable plant cellulose.
• Every year, 2.65 billion holiday cards are sold in the United States. If you're buying, choose cards made from recycled paper and avoid the shiny can't-recycle kind. Even better is to send e-cards. And recycle the nonshiny cards you receive.
• A deluge of catalogs has probably already descended upon your mailbox. It takes 14 million trees to produce the mail-order books we receive annually. And along with direct mailings, catalogs account for more than 4 million tons of CO2-emitting landfill mass. Encourage the catalogs you like to use recycled paper and get off the mailing lists of those you don't want. Read this to find out how.
• Christmas trees are a topic of much environmentalist debate. Fake trees are reusable but are made from petroleum-derived sources and often shipped from abroad. Real trees, for their part, are typically sprayed with lots of pesticides. And new research shows that pine-tree farms capture less CO2 than the hardwood species they're displacing in some parts of the country. Organic Christmas trees are tough to come by. Plus, of the 33 million real Christmas trees sold in North America every year, many end up in a landfill, emitting carbon dioxide as they rot. If you opt for a real tree, be sure to bring it to a local recycling center, where it can be chipped for mulch or used whole to stabilize wetlands. A better choice may be to purchase a live, potted tree, which can be planted outside after the holidays. Evergreen varieties such as pine, spruce, and fir work well in many regions.
• Replace conventional incandescent holiday string lights with their light-emitting diode counterparts. These energy-efficient strings use up to 95 percent less electricity, last up to 10 times longer, and are safer since they produce very little heat. LED lights are more expensive, but you'll shave a few dollars off your electricity bill and pounds off your carbon weight. And unlike conventional light strings, if one bulb goes bad on an LED string, the rest will still work. No matter what type of lights you use, limit yourself to keeping them on for four or five hours a day, and turn them off at night.
• Skip the tinsel and other decorations made from fossil-fuel-intensive plastics.
• For holiday parties, rent real plates, glasses, and silverware (or use your own) instead of using the disposable kind.
• Consider staying close to home rather than blowing your CO2 budget on high-emissions travel to faraway places.
(Click here to take this week's action quiz.)