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Wreaths & Trees
Organic greenery can be hard to find locally, but it's worth the added effort, since organic tree farmers don't use pesticides like glyphosate (Roundup), associated with chest pains and nausea in humans and deadly to many fish and beneficial insects, or organophosphates that can cause convulsions, unconsciousness, tremors and breathing difficulties.

But if you can't find organic, there's no need to stress. "Many pesticides will have been removed from trees by rain and ultraviolet light by the time they are harvested," says Dr. Thomas Arcury, Ph.D., professor of family and community medicine at Wake Forest University School of Medicine. However, he adds, some pesticide residues may remain, so buy from local farmers whom you can ask about pesticide use.

Darthia Farms has fresh, organic and already-decorated balsam fir wreaths for $35. Add mantelpiece greens—organic balsam fir, pine and cedar ($25)—or a centerpiece with three candles ($35; www.darthiafarm.com). For a different take, try McFadden Farm's organic three-herb wreath ($35) or their bay leaf wreath ($22.50), which provide holiday seasonings to your meals long after New Year's Day (www.mcfaddenfarm.com). Or pick Rogue Harbor Farm's certified organic Fraser fir wreaths (from $39; www.localharvest.org; 828-689-4586).

As for the tree, "the most sustainable thing is to be sure you put your dollars towards tree growers that you want to keep in business," says Aubrey Raper, co-owner of Rogue Harbor Farm, which sells organic trees, adding, "By all means cut the tree, enjoy the fragrance and when you're done with it put it in a fish pond to serve as an incubator for young fish."

Or go for potted plants. Sloat Gardens' 11 locations in the San Francisco Bay Area sell potted organic trees ($39.75/1.5 to 3 ft. to $200/6.5 ft.; www.sloatgardens.com). The New Leaf greenhouse in the Bronx borough of New York City sells potted trees, the sales of which support the program's efforts to teach marketable workplace skills to former addicts (www.arguscommunity.org). Elsewhere, visit your farmers' market or check www.localharvest.org for nearby nurseries and organic tree farms. In San Francisco and Portland, you can rent a tree that will be delivered to you, picked up after New Year's, and planted (in Portland, $60, www.livingchristmastrees.org; in San Francisco, see www.fuf.net for prices).

If you can't buy locally, try a 7-ft. Fraser ($89.95) or balsam fir ($79.95) from NorthlandSent Wreath Company, which applies Roundup only between rows (www.localharvest.org, 218-591-0632).