Freshly cut wood is known as greenwood because it still holds a lot of moisture. High moisture content in wood makes it hard to ignite, leads to large amounts of smoke, slows the burning, reduces the temperature of the fire, and can give off fumes which increase the amount of creosote that accumulates on the inside of fireplaces.
Seasoned wood, on the other hand, has a moisture content of less than 20%, ignites easily, burns longer, hotter, and doesn’t produce a lot of smoke.
Seasoning / Drying wood to perfection can take up to 3 years (depending on location and exposure to elements). Although other techniques can speed this process (like drying in a kiln) the most cost-effective way of acquiring wood is to buy it green early spring and season it yourself at home. If the wood is not too green and you store it correctly it might be ready for use 6-9 months later, but probably only really good for use the following winter.
When it comes to seasoning your wood, remember the “Five S’s”:
Carefully research which type of wood you would prefer to season depending on what types of fires you plan to make. Hardwoods, which reach high temperatures and burn slowly, are very dense and, in the case of Gum, can take two years to properly dry out. Softwoods are more porous and therefore the water can evaporate more easily, taking less time for them to dry out (about 12 months). Porous woods also burn faster due to lower density.
The rate at which liquids evaporate increases in proportion to the surface area. Logs of wood are essentially large straws holding water – these need to be split to let the water escape faster. Chopping wood increases the amount of the wood’s surface area to be exposed to the open air and speeds up the drying process all while preventing wood rot and insect infestations.
Wood should be stored in a neat stack (using the right-angles of the split wood to balance consecutive rows) off the ground. A wood stack needs air to blow through it to speed the drying – if the wood sits on damp ground, moisture could seep up into the wood (causing rot) or insects could burrow themselves in the logs. The stack shouldn’t be more than 1.2m -1.4m tall and should be stored where it will be exposed to the sun and a regular breeze.
Choose a wood store location that will not get in your way. Wood shouldn’t be stored indoors as not only does this encourage ants, spiders and mice to enter your home but it will not dry out effectively without contact with the wind and sun. It’s best to store the stack on wood drying racks(so air can flow underneath the wood). Storing wood beneath a roof is preferable, but if not, and in the case of rain, a sheet that covers the top of the stack will do.
The rule of thumb is that most wood requires about 2 x spring & summer seasons to be well seasoned/dry. Usually, if you start drying wood in October, it should be fairly well seasoned by May but optimal by the year following May (2 x spring & summer seasons). Wood cannot be stored indefinitely. After four years wood will start to decay – ensure you use all your seasoned wood within a few years.
How to check your wood is ready
- Wood shouldn’t sizzle or smoke much.
- Dry wood should show some cracks, discoloration and should split from its bark easily.
- When you tap two pieces of dry wood together you should hear a ‘clunk’ sound.
- A fresh, sappy aroma in the wood means it’s still too fresh to burn.