There is no doubt that sky lanterns create a beautiful, magical scene when released en masse at events like parties, memorials and weddings, but there are many concerns regarding their use that go far beyond their aesthetic value. Often scribbled with notes and wishes, paper sky lanterns are traditionally thought to bring good luck. Unfortunately, being made of paper and fueled by an open-flame wax or oil candle, makes them more of a recipe for disaster.

In addition to the paper remains of the lanterns littering the ground once the candles burn out, the sky lanterns pose a significant fire danger. So much so, that they are often referred to by officials as “flaming litter.” Once released, they can climb as high as 3,000 feet before falling back to the ground, and there is no way to have control over the direction that the lanterns will travel.

It is reported that hundreds, if not thousands, of fires around the world have started as a result the flaming lanterns landing on and igniting roofs, trees, the ground, and other structures. In 2011, paper lanterns ignited a fire in Myrtle Beach, South Carolina that burned over 800 acres. In England, cows were killed after eating the remains of lanterns that landed on their pasture. Though it seems unlikely that these little paper lanterns could have such a large impact, planes have even had to be diverted when multiple lanterns flew into their intended airspace, out of fears that they would be sucked into the engines and endanger the plane.

All of these dangers take quite a bit of the magic out of the paper lanterns beauty, but if the fears of fire and aversion to creating litter aren’t enough of a deterrence, at least consider that setting them off is illegal in 29 states, including Maine and New Hampshire.