Plastic Bag Etiquette

Hey Mr. Green,
Should you remove the zipper portions of plastic bags prior to tossing them in the recycling bin? Also, can black plastic bags be recycled with other plastic bags? -- Peter in Easton, Connecticut

Plastic bags are recycled to make durable, long-lasting synthetic boards used for decks and fences. When the plastic is heated up to make it gooshy enough to blend with wood waste and other board material, those thick zipper strips don’t soften as much as the flimsy plastic. This can create clumps that gunk up the board-making process. So rip those zips!

As for black plastic bags, it’s best not to recycle 'em, again because of plastic lumber manufacturing. Once pigment is in a plastic, it's impossible to remove; black plastic can discolor synthetic boards, which makes them a lot less attractive to your average homeowner.

Why do they dye bags black in the first place? It’s not to add an air of sophistication to lugging your 12-pack of Bud Lite. The bags are made of recycled plastic already tainted by a petrochemical rainbow, so black dye makes their color consistent.

Virtue by the Gallon

Hey Mr. Green,
There is an excellent farmers' market 12 miles from our house and a supermarket just 1.5 miles away. Does the 24-mile drive to buy local produce make more environmental sense than a three-mile drive for produce that is not nearly as local? --Gareth in Saline, Michigan

Eating food grown close to home can save transportation energy, but don’t make a fetish of it. For you, a weekly trip to the farmers’ market isn’t all that virtuous, even if the food in your supermarket traveled 2,000 miles. That's because the big rig it rode in needed about a gallon of fuel to move 150 pounds of food that distance. If your car gets 20 miles per gallon, your farmers' market pilgrimage would require almost a gallon of gas more than your round-trip to the supermarket. So you’d have to buy 150 pounds of food at the farmers' market each week to match the energy efficiency of the big, bad corporate food-transportation system. But if that supermarket food is flown halfway across the world, the equation can change drastically. A lot depends on what you’re buying and how it was shipped.

But energy is not the only issue. Farmers at local markets are often good stewards of the land, and direct contact with growers makes it easier to push for cleaner farming practices. Ideally, you should make fewer trips to the farmers’ market; buy lots of stuff when it’s in season; and can, dry, ferment, freeze, pickle, or preserve it for out-of-season use. Plus you could bike to the supermarket -- and even to the farmers' market.