The black locust tree is native to central-eastern parts of the United States and has been naturalized east of the Rockies. While fast-growing, it is vulnerable to disease and pests when stressed.
If you’re considering buying or felling one of these trees, you may be wondering if the wood is any good for burning? In this guide, we’ll take a close look at whether black locust is good firewood. Let’s dive in.
Is black locust good for firewood?
Black locust is one of the best types of firewood available. It offers one of the highest ratings for heat output with excellent coaling properties. This wood will keep your house warm on the coldest winter night.
- A clean-burning fuel that produces plenty of heat.
- Easy to split if the wood isn’t too knotty.
- Low fragrance so not ideal for smoking meat.
- Produces great coals that heat for a long time.
Black locust firewood burn qualities
1. Heat output
When it comes to outputting heat, few types of firewood are as good as black locust. It produces 27.9 million BTUs per cord which is comparable to beech, oak, and apple. Although black locust has a slightly lower BTU output compared to hickory (30.6), it is still excellent wood that’ll provide ample warmth in your home.
To evaluate firewood, looking at heat output will usually be your first consideration. Whether you’re sitting around a campfire or relaxing at home, there’s no point in making a fire if it doesn’t provide adequate warmth.
Check out the following table comparing the heat output of black locust to various other common types of firewood.
| Wood variety | Heat per Cord (Million BTUs) |
| White fir | 14.6 |
| Cottonwood | 15.8 |
| Red oak | 24.6 |
| Beech | 27.5 |
| Black locust | 27.9 |
| Bitternut hickory | 29.2 |
| Shagbark hickory | 30.6 |
| Gambel oak | 30.7 |
| Rock elm | 32.0 |
| Osage-orange | 32.9 |
2. Smoke
It’s all very well to have a hot fire, but some wood gives off smoke like a steam engine. You’ll end up with a smoked-out house and sore eyes.
Seasoned black locust burns clean, emitting very low levels of smoke. Whether you’re sitting in the comfort of your own home or huddled around a campfire, smoke won’t be an issue.
Keep in mind that the firewood needs to be adequately seasoned before burning it. Green wood is high in water content and will billow out smoke if it’s tossed into the fire. Unseasoned wood is also much less efficient as the fire uses all its energy to evaporate water instead of giving off heat.
3. Ease of splitting
In general, black locust has a straight grain with a medium texture that is easy to split. To make life easier, we recommend investing in a splitting axe or maul that’s made for the job.
Discussions on forums about how easy a certain variety of wood is to split are always contentious. Usually, the reason no-one agrees is that some wood is straight while others get landed with the crotch. That’s the area where several limbs come together into one gnarly, knotted mess. If you get landed with the crotch, then forget splitting the wood by hand and use a hydraulic splitter.
If you decide to split wood manually, then start on the outer 6 inches of each round. “Peel” the round like an onion until you reach the center.
4. Sparks
Some wood species, like mulberry and larch, are known for firing off a lot of sparks as they burn. Inside a wood stove, some enjoy the fireworks display; but if you’re camping or have an open hearth, too much popping and sparks can create a fire hazard.
Black locust will produce very few sparks, so you can light the fire and relax. Of course, if you’re in the outdoors then you can never be too careful. Never leave a burning fire unattended as it can be unpredictable.
5. Aroma
Black locust doesn’t give off any fragrance as it burns, unlike some other popular firewood like cherry. For many, this won’t be a deal-breaker as the subtle smokiness that any fire gives off is enough.
Meat smokers and barbecue enthusiasts may want to combine black locust with another variety of firewood like apple or hickory. You’ll get excellent coals for cooking as well as food with amazing flavor.
6. Coaling
The quality of coal produced by firewood impacts how well a fire burns and how long the fire will last.
Black locust ranks in the top few for coaling. Place a large log on the fire and it should keep you warm all night.
As a bonus, next day re-starting the fire is quick and easy thanks to the embers that’ll still be glowing.
7. Creosote build-up
Creosote is a type of black tar that slowly gets deposited on the inside of chimneys as the fire burns. Hardwoods like black locust are known for low levels of creosote, which is great as you won’t need to clean out the chimney as often.
Related reading
How long does it take to season black locust?
Allow at least 12 months to season black locust, although in less dry areas 24 months is preferable. Burning firewood too soon will result in smoky fires that don’t reach anywhere near their heat potential.
Seasoning time will be greatly reduced if you can find old black locusts that have been dead for years. They’ve already dried out so you may only need to season this wood for 6 months.
Tips for seasoning black locust
There is a range of options for speeding up the seasoning of black locust. Living in a hot, dry climate is a good starting point. You can accelerate the drying time further by following these tips:
- Create gaps in the rows: build a series of stacks with a 3-5” gap between each one to help circulate the air.
- Cover the wood: use a tarp or something similar to protect the stacks from rain and snow while keeping one side exposed to the wind.
- Stack in the right place: speed up drying time by facing the stack towards the wind and avoiding shady areas.
- Split the firewood: splitting the logs will increase the surface area that gets exposed to sunshine and wind.
- Raise the wood: lay the wood on some planks or pallets to create airflow beneath the wood.
Common locust tree varieties
There is a range of different locust species growing in many parts of the world including Europe, China, and the United States. The following are some of the more common species:
Frisia black locust
A fast-growing variety that can reach heights of 50 feet with a spread of 40 feet. This is a drought-tolerant tree that produces fragrant white flowers in late spring and through summer.
Tortuosa
The tortuosa only reaches 20 feet tall and is a gnarly tree with many twisted branches. It is a common variety that is popular for firewood usage.
Purple robe black locust
The purple robe is a popular choice for landscaping as it is compact with leaves that change through each growth phase. Purple robes have pinkish, rose-like blooms that look stunning. These trees have a relatively short lifespan; if you have one on your property, it may be ready to fell for firewood.
Twisty baby black locust
The twisty baby is a much more compact tree that grows to 20 feet in height. This tree is easily identified by its contorted limbs and fragrant white flowers that bloom in summer.
Commonly asked questions
When is the best time to chop black locust for firewood?
It is best to fell a black locust tree and process it for firewood between winter and early spring. During this cold part of the year, there is lower sap and moisture content, resulting in wood that seasons quicker.
Is black locust good for smoking meat?
Black locust has no aroma and isn’t recommended for smoking meat as your food won’t get any additional flavor. Better options for meat smoking include hickory, cherry, or apple.
How long does a cord of black locust last?
The length of time a cord of black locust firewood lasts will vary depending on the climate you live in, the fire you’re using, and how well the wood is seasoned. In general, expect one cord to last between 6-8 weeks, enough time to get you through the coldest snap.
How can I identify a black locust tree?
To identify a black locust tree, look for thorns growing near the origin of the leaves. You can also check that the leaves that grow along branches in a left-right pattern (alternate compound). You’ll notice the leaves have many leaflets, ranging from 9-19 on each compound leaf.
How can I identify black locust firewood?
Identifying dried black locust is a little trickier than if you’re dealing with a live tree. Look at the bark for signs of small ridges or warps. You can also check the weight of a round – if it’s heavier than other common wood like oak, then it’s more likely to be black locust.
Fast facts
- The botanical name for black locust is Robina pseudoacacia; it is from the family Fabaceae – Legume.
- Black locust cultivars include purple robe, Aurea, Fibermaster, Lacy Lady, Unifoliola, Bessoniana, Dean Rossman, Frisia, Umbraculifera, and Tortuosa.
- Some consider the tree invasive as it grows quickly and has thorns.
- Learn more about the black locust here.
Summing up
Like any firewood, its quality will vary depending on the species, the way it has grown, and seasoning time. In general, black locust is one of the top few types of firewood. It burns clean and hot, with coals that’ll keep you warm all night.
If you’re looking for firewood with a nice fragrance, then black locust won’t be an ideal choice. It has little or no smell and won’t be ideal for smoking food with. Be sure to check out our articles on mulberry or walnut if you want nice smelling firewood.
