Autumn often turns people’s thoughts to cutting and buying firewood for the winter.

For the most heat for your time and money, burn dry firewood.

“The higher your firewood’s moisture content, the less efficiently it burns,” explained Larry Giardina, energy agent with the Oregon State University Extension Service. “If you don’t let it dry long enough under the right conditions before you burn it, you’ll get a smoky fire without much heat.”

The smoke from a low-temperature fire contains gases and acids that condense on your chimney to form creosote – a substance that can ignite and cause a major fire, said Giardina.

Beside giving off less heat, burning green wood means you have to clean your chimney more often. It also means you’ll have to work harder to get your fire going.

“Some of the wood’s water must boil and evaporate before the wood will support a flame,” he said. To avoid the hassles of burning green wood, Giardina advises:

? Season firewood until it contains less than 20 percent moisture. This generally takes six to eight months, depending on the weather, the type of wood and how you prepare and store it. Hardwood such as oak takes longer to dry than softwood like Douglas, fir, or pine.

? If you cut your own firewood, do it each year by late winter or early spring in order to allow enough drying time during the hot, dry summer months for moisture to move through the wood’s fibers and evaporate. If you buy firewood, buy it dry. It might cost more, but will start more easily, give off more heat and burn cleaner.

? Split wood right after you cut it. It dries faster split. Remember to cut kindling, too, and let it dry.

? Stack firewood off the ground to allow air to circulate under the stack and around the pieces. Crossing the wood log-cabin style promotes good air flow within the stack. Do not stack wood directly up against an outbuilding or house.

A simple and effective way to stack and shelter firewood is on a pallet, stacked log cabin-style, with a sheet of clear UV – inhibited polyethylene draped over the top of the stack to allow sunlight through to heat the stack. Leave the sides open to allow air to circulate. Secure the polyethylene with a few pieces of wood or rocks. Once the firewood is dry, replace it with a sturdier nylon or canvas tarp.