Of course, do not put burning candles on or near the tree. Make sure the tree cannot fall over into an open flame or heater which can ignite the very flammable tree. Have a joyful Christmas with your safe, New Mexico Christmas tree. This is an interesting question. I assume you are asking about lawn grasses, but first I want to discuss grasses in general.
Some grasses are annual grasses.
These annual grasses live for a single growing season and die. They are genetically programmed to die at the end of their growing season. Our common lawn grasses are usually perennial grasses. That means that they grow for several years. As long as the weather is unfavorable, they remain dormant.