The size of your log really does matter.

The biggest and hardest log is most coveted for the traditional holiday Yule log. Its purpose was to provide a long and hot burn for the family festivities. The objective was to provide for 12 hours, though some say 12 days, of burning.

It is more than just a log that has been conventionally used for this holiday ritual. In fact, in the early days of the Yule log, an entire tree, carefully selected for warmth and longevity, would have been cut from your property and dragged into the house for the tradition. The trunk end would be put into the hearth and the rest of the tree would stick out into the room to be slowly fed into the fire. What a mess that would make!

This practice is one of the oldest holiday traditions known, predating Christmas. It originated in Scandinavia during the solstice festival Jol (pronounced Yule) that honored the Norse deity Odin — the god of intoxicating drink, ecstasy and death. On the holiday a sacrificial beer was drunk that was purported to protect the drinker from witchcraft.

During the celebration, no work was to be done when the Yule log was burning in the hearth — another reason why a large log was preferred. The burning wood was representative of the coming of additional light from the sun, the approach of longer days, the burning of faults and mistakes, and the beginning of a good and lucky new year.

Eventually Christianity came into the picture and adopted the Yule log custom. In the fourth century, Pope Julius explained that the burning of the Yule log actually represented the light of the Savior.

The Yule log had other names, including the Christmas log, clog log, block log, Gule block or stock of the mock. Different types of wood were preferred in different countries. The British selected oak as their Yule log, while the Scottish liked birch. In France, cherry was used and the log was salted and covered with oil and wine. The French even make wood sound delicious, though likely it was the pleasant smells from the additions that were desired.

Sometimes chemicals were sprinkled on the logs to make them burn in color. Potassium nitrate produced violet, barium nitrate showed apple green, borax yielded vivid green, copper sulfate begat blue, and table salt encouraged a bright yellow color to show in the flames.

The lighting of the log was not without ceremony. It had to be lit with splinters from last year’s log that had been stored under the bed. Only the daughter or mother of the home could do the lighting.

If the burn didn’t last long enough, tragedy would strike the household. Watch out for the flames, too, for if they cast a person’s shadow without their head, that person would die during the year.

It was important to keep a piece of the wood, or splinter, to light next year’s log, and to also properly dispose of the ashes after the burn. Adding the ashes to the garden was good for its fertility and promoted a great harvest.  Dropping ash in the well made the water sweeter. Some even used the ash in amulets for yearlong charms meant to protect the house from lightning, fire and the powers of the devil.

Times did change and the Yule log began to fall out of favor due to the decline of agriculture and the loss of open hearths in homes. Some cultures, however, have kept the tradition alive in other ways.

Those French are again to be commended, as they created a Yule log dessert called a bûche de Noël, that consisted of cake and chocolate mousse rolled into a log shape. (Once again, the larger of these, the better!)

Then there are the Americans whose version consists of a burning log, accompanied with Christmas songs, that was shown on TV from the late 1960s through the present time. With technological advances, we can now watch the burning log on DVD, download it onto our computer or handheld device, or listen as a podcast. Ah, American culture! No matter how you get your fix of flames, enjoy the warmth, beauty, history and symbolism behind them. Don’t let the spark go out after the holiday; there are plenty of reasons to keep the home fires burning. Suzan Bellincampi is director of the Felix Neck Wildlife Sanctuary in Edgartown.