Throughout history, firewood has been a heat source and continues to play a significant role in modern times, heating homes, creating cozy moments by the fireplace, and facilitating cooking sessions.
Knowing how firewood is classified is important for those seeking efficiency and safety when using wood for fuel.
Firewood is typically categorized based on the type of tree species used to make it along with factors, like moisture content and the resulting heat output and burn qualities.
Let’s explore how firewood is sorted and classified.
Distinguishing Between Types of Trees Based on Species Classification
Firewood is often categorized based on its species into two main types: Hardwood and softwoods.
Hardwood
Hardwoods are derived from trees that shed their leaves yearly and are known for their density and weight compared to softwoods. They burn at a rate and generate more heat. Common hardwoods used for firewood comprise…
Oak trees
Oak trees are popular because they burn for a long time and produce a lot of heat efficiently. Making them a top pick, for those living in colder regions.
Oak wood is known for its burning capabilities and clean combustion which makes it a great choice for keeping warm and preparing meals.
Maple wood
Maple wood is known for its burning properties and delightful fragrance which makes it a favorite choice for use in indoor fireplaces.
Birch
Birch burns rapidly. Emits a vibrant flame and intense heat which makes it ideal for brief fires. I enjoy the smell of cut pine and cedar.
Softwoods
Softwoods are sourced from trees, like pine. Spruces typically have needles and cones attached to them. They tend to be less dense compared to hardwoods which makes them burn quicker and produce heat. However, I find softwoods to split and light up. Some examples of softwoods include;
Pine wood
Pine wood is easily accessible and ignites effortlessly—perfect, for starting a fire or as kindling material; however it burns fast. May generate excess creosote that could cause buildup in the chimney.
Spruce trees
Spruce trees are like trees in that they are lightweight and burn fast; however, they are great, for starting fires as well.
Fir trees
Firewood from fir trees burns steadily. Produces a consistent amount of heat which makes it versatile, for various uses.
Classification by Moisture Content: Green Wood vs. Seasoned Wood
The effectiveness of firewood is greatly influenced by how moist it is, with firewood being categorized as either green (unseasoned or fresh-cut wood that still retains moisture) or seasoned (dry wood that has been properly dried).
Green forest.
Freshly cut wood with the high moisture content of around 30 to 50%, known as wood is not recommended for burning due, to the following reasons;
Reduced Heat Emission; A significant portion of the energy is lost due to the evaporation of water resulting in a decreased heat output.
Burning wood creates extra smoke that can be bothersome and result in the accumulation of creosote, in chimneys—a situation that could pose a fire risk.
When wood is green and has a high moisture content it becomes challenging to light it up and keep a burn going.
Aged timber
Dry wood that has been seasoned by air drying or in a kilnThe moisture content of seasoned wood is reduced to 20 percent or lower this type of wood is favored for burning due, to its properties
Increased Heat Production; When there is a reduced amount of water to evaporate a greater proportion of energy is transformed into heat output.
Burning wood results in a cleaner burn, with less smoke and lower chances of creosote buildup occurring.
It’s simpler to start a fire with wood as it catches fire more effortlessly and burns steadily.
Categorization based on Heat Emission Levels as measured in BTUs (British Thermal Units)
Good firewood can be categorized by how heat it gives off in British Thermal Units (BTUs). Firewood with BTUs produces more heat per cord and is better, for heating purposes.
High BTUs Dense woods with BTUs like oakwood hickory and maple are great for keeping fires burning long and hot during chilly winters.
Medium BTUs Some types of wood with BTUs are birchwood and cherrywood which provide a good mix of burning duration and warmth, for average heating requirements.
Low BTUs are found in types of wood like pine, fir, and spruce. Although these woods ignite easily and are great for starting fires they burn fast. Produce less warmth, which means they aren’t as effective, for heating purposes.
Classifying based on how Wood burns
Various types of wood display burning behaviors that can impact the kind of fire they create.
Long-Burning Wood: Hardwoods such as oak, hickory and beech are known for their lasting burn that provides steady heat making them a great choice for keeping warm overnight.
Quick Burning Wood: Softwoods such as pine and cedar are known for their ignition and fast burn rate; they are great for starting fires or generating rapid bursts of heat.
Aromatic Wood: Certain types of woods, like cherry and apple, emit scents when they are burned which is why they are commonly preferred for indoor fireplaces and cooking purposes.
Low smoke Wood: Certain types of hardwoods such as ash produce smoke when they are burned making them ideal for indoor use.
In summary
Understanding the categorization of firewood is crucial when choosing the wood for your requirements – whether you’re warming your house or cooking or simply having a cozy fire outdoors for leisure purposes. Hardwoods are commonly favored for their ability to burn longer with heat levels compared to softwoods which are more suitable for fast fires and starting kindling. Seasoned wood is always the option, over green wood as it offers better efficiency and a cleaner burning process. Knowing these categories can assist you in making choices to maximize the warmth and safety benefits of your firewood.
