Is Elm Good Firewood?

An important tree to many forests in the northern hemisphere, elm (Ulmus procera) is a wood you are probably very familiar with. It can live to be 100 years old, as long as it doesn’t contract Dutch Elm Disease. How does a good, healthy elm serve as firewood?

Elm is excellent firewood that should not be ignored. The elm varieties with a slightly lower BTU are ideal for warming your home, presenting very few issues. It may be a difficult wood to process but the heat it provides is well worth the effort. 

What Are The Varieties Of Elm?

There are around 40 species of elm available all over the world. They are categorized by hard and soft elm and include red elm, Siberian elm, and American elm.

However, two species stand out as good firewood.

Cedar Elm

As one of the hotter burning elm firewood, cedar elm (Ulmus crassifolia) is very common to the south of the US.

It has a BTU of 26.8, which is efficient but can be too hot if not monitored.

Chinese Elm

Also known as the lacebark elm, Chinese elm (Ulmus parvifolia) has lower burning heat than cedar elm. However, this makes it excellent firewood as it doesn’t get stiflingly hot.

Chinese elm does tend to grow smaller than cedar elm, so you won’t get as much firewood out of it. But the firewood you do earn will be brilliant.

What Are The Physical Characteristics Of Elm Wood?

Name	Elm
Heat per cord (Million BTUs)	22.9 – 26.8
Weight dry (lbs per cord)	3182 – 3890
Weight green (lbs per cord)	4590- 4760
Seasoning time	1 – 2 years
Resin/ Sap Content	Low
Splitting Difficulty	Difficult
Smoke	Moderate – High
Smell	Can Be Unpleasant
Coal Production	Good
Creosote Build-up	Little- Moderate

Is Elm Easy To Split?

Even for a hardwood, elm is very difficult to split.

Elm grows similarly to dogwood but is harder to split than dogwood. It grows with an interlocking grain that resists splitting while also being a dense wood, so splitting through the interlocking grains is a hard task.

How Much Sap Content Does Elm Have?

Hardwoods typically have a low sap content within their wood. Elm follows this trend, with little sap.

Even the softer elm varieties still lack sap. Especially when compared to the notoriously sappy pine wood.

What Does Elm Smell Like?

Elm absorbs the smell of the environment that it grows in.

So, if you find an elm growing next to a boggy swamp, it will probably smell awful. Though elm that has grown in a daisy field full of sweet-smelling flowers will smell great.

As a species, elm is prone to diseases. Dutch elm disease will leave an elm with an awful scent. Keep an eye out for the signs of a dying elm to prevent bringing unpleasant smells into your home.  

Heat Output And Efficiency Of Elm

Elms that are categorized as harder woods (e.g. cedar elm) have a more efficient heat output of up to 26.8 BTU. Whereas softer elms like Chinese elm burn a cooler with a BTU between 21.9 – 22.5

Though they are often separated in terms of wood density and BTU, all elm is hardwood and so has a higher heat output than softwoods.

For example, fir varieties can only reach a BTU of 18.9 on a good day.

Fire Characteristics Of Elm

Due to the density of elm, it can produce some very high-quality coals.

For a wood that is not as dense as hickory or hotter oak varieties, elm’s coals are just as effective as other hardwoods and will keep your fire burning through the night.  

Being a wood that harbors low levels of sap and resin, you will not need to worry about excessive sparks coming from an elm fire. So, you can leave a fire going for long periods without any worries, even outdoors.

You will want to ensure that the hotter burning elms do not get too hot during the night, though. Perhaps favor Chinese elm if you wish to stack a bit more into your fireplace than usual.

Does Elm Burn Clean?

Just like with its scent, elm absorbs whatever water it comes into contact with while growing. An elm growing in well-moistured soils will retain a lot more water than elms growing near the sand.

Regardless of how much moisture an elm has, it does season well and will only produce a moderate amount of smoke, resulting in less creosote. This makes it semi-clean burning wood.

There are plenty of other woods like poplar which are worse for burning than elm. However, if you do not season elm for long enough, then it will smoke terribly.

By burning green elm, your wood will create high amounts of smoke which will result in a quicker build-up of creosote.

Is It Okay To Burn Elm In A Fireplace?

Elm is good firewood to use in your fireplace, so long as you have seasoned it beforehand.

In terms of heating your house, Chinese and American elm will serve you well. It will not produce a stifling heat but will keep your home comfortable through the winter months.

If you opt to burn an elm with a higher BTU such as cedar elm, make sure that you maintain the fire well. Otherwise, it will get too hot, and potentially damage your stove or a fireplace.

You may want to use softwood to help get an elm fire going as it does not take to flame very quickly. Using poplar or pine kindling will help ignite your elm.

How Long To Season Elm Wood?

How long you need to season elm wood will depend on where you got the wood from and how much water it has absorbed.

Check the elm wood’s surroundings when you gather it to determine how long you may need to season it for.

On average, you can expect elm to take 1 – 2 years to reach a less than 20% moisture rate. For elm more prone to high levels of moisture such as Chinese elm, you may need to wait 3 years before burning it.  

Unseasoned elm is very smoky and can smell unpleasant so ensure that your elm firewood is fully seasoned before use.

As for storing seasoned elm, you will want to keep it far away from moisture. Even seasoned wood, including elm, will absorb water close by and start to rot. To prevent this, keep elm dry and away from other firewood.

Pros And Cons Of Using Elm as Firewood

Pros:

• Very efficent heat output
• Widely available
• Low creosote build-up
• Good quality coals

Cons:

• Difficult to split
• Can smell awful
• Hard to prepare
• Prone to rotting

How Does Elm Compare To Other Firewood?

Even the denser hardwoods do not typically take as long to dry as highly valued oak varieties.

However, it is one of the more difficult woods to prepare for just as an efficient heat as ash firewood which is often easier to prepare.

Unlike hotter burning hardwoods, elm has cooler species that will not over-heat your home nor fireplace when burnt for hours. Though even the soft elms like Chinese elm will need to be mixed in with poplar or fir to ignite.

Frequently Asked Questions:

How To Spot A Diseased Elm? 

The last thing you want to do is burn an elm diseased with dutch elm disease.

If you find elm branches with leaves that are turning yellow or bark is yellowing, that could be a sign that the wood is diseased.

What Is the Best Way To Store Elm?

Keep elm away from water by storing it off the ground and somewhere that a breeze can reach it. Like with other firewood, having elm stored close to your home will also ward off any potential beetles or bugs wanting to make their home in your firewood.

Do Softwoods Or Hardwoods Make Better Firewood? 

Typically, hardwoods make better firewood as they are denser and can give off more heat for a longer amount of time. Some softwoods can also burn hot and are still used around the world, like douglas fir firewood, but they burn for a shorter amount of time and their fire characteristics are not as appealing.

Conclusion

Elm can make excellent firewood as long as it is seasoned long enough and is not diseased. However, be cautious of the denser elms (cedar elm, rock elm) as they can burn too hot if not monitored.