Send your question to Umbra! Q. Dear Umbra, Which is greener -- real Christmas trees or fake? I know you answered this question in the past, but I wonder if there's any new data? Ginger C. Littleton, Colo. All this tree needs is a little love.A. Dearest Ginger, Of the many wonderful and cherished traditions we honor this time of year, just one has earned a secure place in my heart: the Great Christmas Tree Smackdown. The short answer is, live trees are greener. The longer answer is, entire industries are waging battle over this question, the greenness of any …

Send your question to Umbra! Q. Dear Umbra, I just heard an ad for hair-care products that are allegedly "certified hypoallergenic." There's no such thing, is there? And is it illegal to make that claim? Shirley C. Wynnewood, Penn. A. Dearest Shirley, Hark! The holidays are here, and many of us might soon find ourselves in situations where we need to look sparkly and shiny, and even smell marginally pleasant. Your letter is a good reminder that we should be careful what we slather on our bodies. Many makers of beauty products have an ugly reputation when it comes to …

Send your question to Umbra! Q. Dear Umbra, Our Occupy group is looking for information regarding the safety of using wooden pallets. They want to use them under tents, to help stay drier, and possibly to burn (for heat only, not for cooking). I found a Grist article on pallets from a few years ago, but wondered if there's any current information. Thanks! Sylvia P. Haynesville, La. Photo: Merv StapletonA. Dearest Sylvia, How it warms my heart to think of you down there in Louisiana, taking a break from chanting about democracy to check the Grist archives. My reply comes …

Send your question to Umbra! Q. Dear Umbra, When I was in college, I had a friend who thought she was eco-conscious, but she used to crank the heat and then leave the windows open for "fresh air." Years later, I dated a woman who lived in a building where the heaters were stuck on high and the windows were all open. Fast-forward to now: My wife likes to have the radiators on with the windows open ... for the ventilation. While this seems obviously a waste of money and bad for the environment, I don't have the facts to …

Send your question to Umbra! Q. Dear Umbra, Does polyester ever break down into molecules that return to the natural state? Does dyed wool compost? Evelyn P.Powell River, B.C. A. Dearest Evelyn, You pose two good questions, though the more I peer into the murky world of textile production and disposal, the more I want to simply curl up in an organic B'leeve (my soon-to-be-trademarked version of the Slanket) for the rest of my time on earth. It seems you want to find creative ends for some clothing, and I applaud you. I would also like to remind all my …

Send your question to Umbra! Q. Dear Umbra, If I ever manage to lose these rolls and handles, will the toxic stuff I'm storing in my fat be released? Will I get sick in the process? Theodora S.Angel Fire, N.M. A. Dearest Theodora, Yours was the closest I could find to a Halloween question this year, what with the health concerns this overindulgent holiday brings. Plus: Scary topic! Boo! Before I proceed, the usual disclosure: I am not a health professional, nor have I ever played one (or even been in the running to play one) on TV. Please take …

Cherry-pick your food containers and leave plastic baggage behind.Photo: Elvis KennedyDearest readers, Once in a while, your separate letters decide to link arms and chant in unison to ensure that they're really heard. Today they are telling me that many of you are losing sleep over plastics and food. But may I gently suggest that your insomnia is misplaced. Instead of gazing into the darkness and wondering whether you should wash out your zip-lock baggies, you should be chewing your pillow in fury over the fact that a household good could be so bad. The plastics industry, built on the …

Send your question to Umbra! Q. Dear Umbra, Is it legal for the neighborhood ass. to forbid a clothesline in the area of residence which it controls? Bill H.Titusville, Fla. Photo: PeppysisA. Dearest Bill, I was going to spell out your abbreviation for association, but I decided to let your (perhaps intentional) shorthand stand. Because yes, it is legal in many places to ban clotheslines, and ass.es across the country do just that. Why? They don't want to look at your underwear. That's the long and short of it, although cited reasons include safety, property values, and public nuisance concerns. …

Send your question to Umbra! Q. Dear Umbra, Recently I was in an airport and saw drinks in bottles touting "plastic made from plants." What's up with that? Most plastic is made from oil, and that technically came from plants, once upon a time ... are these new bottles just a bubbly reframing of business as usual? Scott R.Seattle, WA If only it were this simple. Photo: Peter RowleyA. Dearest Scott, I have chosen to answer your question for two important reasons: 1) It represents one of modern life's many eco-conundra, and we should all be armed to respond in …

Send your question to Umbra! Q. Dear Umbra, My car seats are going to expire in the spring. I know where to recycle the metal and fabric components, but what about the big chunk of plastic that is the car seat itself? I've heard of recycling events in other cities, but no one here in NYC seems to think they are recyclable. Could you please tell us if there is some national list of places that will recycle expired car seats? CristinaBrooklyn, N.Y. A. Dearest Cristina, Your letter gets at a situation stickier than a 2-year-old with an ice cream …