Here's how to choose the best tree for you, put it up straight without a struggle, and keep it fresh, fragrant, and hazard-free -- plus, postholiday cleanup and ornament storage tips. Tree-Buying Tips The Top Tree Types Keeping It Fresh Seven Must-Follow Safety Rules Taking It Down The Smart Way to Store Your Ornaments Tree-Buying Tips 1. Measure the height of the ceiling in the room where you will display your tree. Choose a tree that is at least one foot shorter than the ceiling height (take a tape measure with you). Also, it's best to measure the opening of your tree stand and make sure the base of your chosen tree will fit. 2. Run your fingers along the needles and give the tree a shake. If the tree is fresh, the needles should be pliable and no more than ten should fall off. 3. Make sure the base of the tree is straight and at least six inches long, so it will fit easily into the tree stand. The Top Tree Types For a beautiful shape, lush branches, rich color, and superior needle retention, choose one of the five Christmas-tree varieties below, says David Stenger, manager of the National Christmas Tree Association and owner of Sinnissippi Forest, a choose-'n'-cut tree farm in Oregon, Illinois. If you're having trouble locating the perfect tree, the Canadian Christmas Tree Association can refer you to your local association for a list of tree farms in your area, as well as farms that specialize in living Christmas trees (call 613-789-7846). Balsam fir: The most traditional Christmas tree, the balsam fir is very aromatic with short, 1/2-inch needles and a tall, slender shape -- perfect to tuck into the corner of a room. Douglas fir: A very full, graceful tree with an even silhouette and slightly longer needles than the balsam. Fraser fir: Very similar in shape to the balsam but with 1/2-inch to 2/3-inch needles that are a beautiful dark green on the top and silvery underneath. Noble fir: A lovely layered tree that's extremely aromatic, with short, 1-inch needles. The species is native to the West Coast, but is gaining popularity throughout the U.S. It is similar in shape to a Douglas fir but is a deeper, richer green. Scotch pine: Though native to Europe, the Scotch pine is the number one-selling tree in the U.S. One reason: Its branches curve upward, making them perfect for hanging heavy ornaments. It's also a very pretty, full-shaped tree with deep green soft needles that can be as long as 3 inches. Keeping It Fresh Here's how to maintain your tree's fragrance and prevent mass needle fallout: • When you buy your tree, have an inch cut off the base to make it easier for the tree to take in water. (Be sure the cut is straight so the tree will stand up properly.) • If you don't plan to put the tree up right away, place the tree in a bucket of warm water and stand it in an unheated garage or porch away from the wind and cold. • When you bring your tree inside, use a stand that holds at least one gallon of water. • Keep your tree well-watered. Water prevents the needles from drying and dropping off and maintains the fragrance. Trees may use several quarts a day, so check the water level in the stand every few hours. • Never let the water level fall below the base of the tree or the cut end may seal over, preventing further water intake. If this happens, take the tree down and make a fresh cut. • Don't add anything to the water. Though some people swear that throwing in such extras as aspirin, soda water, bleach, salt, sugar, or Karo syrup keeps trees fresher longer, the experts say plain water, and plenty of it, is best. Seven Must-Follow Safety Rules This season, keep your home safe from some common Christmas-tree hazards by heeding these important tips from the National Safe Kids Campaign: 1. Never place your tree near a heat source, such as a fireplace or portable heater. 2. Trim the lower branches to avoid eye injuries if you have small children or pets. 3. Hang all ornaments that are breakable, have small, detachable parts or metal hooks, or that look like food or candy on higher branches where small children can't reach them. Green floral wire, which can be twisted firmly around branches, is a great way to hang fragile ornaments. 4. Keep pets out of the room in which the tree is placed, especially if you can't be there to supervise. Cats are notorious for leaping onto Christmas trees, especially when pursued by another pet. Keep the tree from toppling by tying it to a ceiling hook. Both cats and dogs can knock down and break glass ornaments, then cut themselves on the pieces. Pets may also gnaw on electrical cords for Christmas tree lights. So hide them when possible, or help prevent injury by purchasing a pet-proof conduit. 5. Avoid using artificial snow sprays, which can cause lung irritation if inhaled. 6. Turn off tree lights when you go to bed or leave the house. Use only UL-approved electrical decorations and extension cords, and check to be sure no cords have frayed since you last used the lights. 7. Never burn Christmas-tree branches in your fireplace. It can cause the buildup of creosote, a highly flammable compound. Taking It Down The best way to avoid a major mess is to prepare to take your tree down before you even put it up. Just place a plastic tree bag (available at hardware stores) underneath the stand, which you can hide with a tree skirt. Then, when the holidays are done, pull the bag up around the tree, stand and all, and carry it outside. Remove the stand before recycling the tree. If some needles do scatter inside, sweep them up; needles can clog vacuum cleaners. The Smart Way to Store Your Ornaments Whether they're heirlooms passed down to you from your great-grandmother or homemade treasures your kindergartner crafted, ornaments need to be stowed with care to maintain their pristine condition for next Christmas. Here's how: Choose the correct container: The experts at Silvestri, a top manufacturer of holiday decorations, recommend storing ornaments in sturdy, partitioned cardboard boxes. You can buy these, but the sectioned boxes you can obtain for free at liquor stores work just as well. Forgo plastic containers; they don't allow air flow, so moisture can become trapped and damage the ornaments. Wrap them right: Protect your ornaments before boxing them by wrapping them individually in acid-free tissue paper or 100 percent cotton cloth. Don't overstuff the compartments or you'll risk crushing the contents. Find the ideal spot: Ornaments should be kept in a cool, dry place. So skip the attic (extreme temperatures can cause paint to flake) and the basement (dampness and mildew can cause irreparable damage). The best choice is an upper shelf in a closet where they can remain undisturbed until next December. PHOTOS (DECORATED TREE, ORNAMENTS): © Mark Thomas PHOTOS (TREE TYPES): © National Christmas Tree Association