"It's the most wonderful time of the year," legendary singer Andy Williams and many others after him have crooned about the holiday season. Well, it may not be so wonderful if you're a seasonal allergy sufferer. According to the Asthma and Allergy Foundation of America (AAFA), three out of four adults experience an increase of allergy attacks including headaches, eye irritation and sinus congestion during the period from Thanksgiving through New Year's Day. Here, a rundown of the five biggest allergy triggers of the season-and how to keep them from turning you into a Scrooge.

1.  Trees and decorations. Allergies to evergreens are usually caused by high levels of mold spores, grass, ragweed, and pine pollen-all of which can trigger severe symptoms including asthma attacks. Artificial trees aren't much better, though, if they're stored in areas where mold can grow throughout the year. The same holds true for ornaments and other decorations that are packed away yearly. To avoid mold contamination, store decorations and artificial trees in dry, temperature-controlled areas, and seal the cartons tightly. When unpacking, open cartons outside or in the garage, and allow them to air out for 24 hours before bringing them into your living area. If a live evergreen is something you simply can't live without, the AAFA suggests wiping the tree trunk thoroughly with a solution of lukewarm water and diluted bleach (1 part bleach to 20 parts water) to eliminate any mold. And before bringing the tree inside, use a leaf blower (in a well-ventilated area away from the house or garage) to remove visible pollen grains.

2. Poinsettias. This traditional Christmas plant produces a milky sap that may cause contact dermatitis or skin irritation in some people. Interestingly, poinsettias are in the same family of plants that produce natural rubber latex (used to make gloves, balloons, condoms and other products), and so people who are allergic to latex products may also experience allergic reactions to poinsettias. Instead, opt for artificial plants, although be sure to wash them off if they were stored away during the year.

3. Scented candles. As irresistible as the fragrances of gingerbread cookies or candied apples can be, they may come at a steep price to allergy sufferers. According to experts at the Washington University School of Medicine, people with nasal allergies have a natural increased sensitivity to fragrances, so they're likely to get a runny nose or watery eyes around candles. Smoke from candles can also be an irritant. To avoid the sensitivity that comes from snuffing it out, open a window or blow out the flame outside. And when shopping for candles, opt for the fragrance-free variety.

4. Alcohol. The celebratory feeling of the season may put you in the mood to kick back a few, but the result could be an allergic reaction (not to mention a nasty hangover.) Certain ingredients found in alcohol, such as wheat and sulfur dioxide, may cause you to develop a rash, headache, or a stuffy nose-not exactly the state you want to be in when trying to make a good impression at your office holiday party. Instead, opt for non-alcoholic (but still festive) options such as a Shirley Temple or apple cider.

5. Firewood. There's nothing more picturesque than cozying up in front of a wood-burning fireplace with the snow falling gently outside. But if you're prone to allergies, that pretty picture can turn pretty ugly pretty fast. Wood from outside can carry everything from mold and fungus to dirt and bugs, all of which can aggravate your allergies. What's more, an improperly-circulated fireplace can permeate the odor of the wood, aggravating your symptoms. To reduce your risk, carefully inspect the wood before bringing it inside-and be sure to clean out your fireplace regularly. Or better yet, consider using gas logs so your living room can still retain that cheery glow and winter warmth.