Most people think of nuts when they hear Walnut trees, but don’t overlook the fact that Walnut trees can be a great source of firewood for you.

Walnut is good for firewood because it is a clean burning hardwood that produces an adequate amount of heat. It has a pleasant aroma and is easy to split. If you are lucky to have Walnut growing near you, I would take advantage of the opportunity.

Keep reading to learn more about Walnut and what makes it a great choice for firewood.

Common Characteristics of Walnut Trees

Walnut trees are a hardwood and are known for the tasty nut they produce. There are many different species of Walnut trees but they all have a few common characteristics that make them stand out from other types of trees.

Leaves: Walnut leaves are feather-like and mirror each other on opposite sides of the leafs axis.

Size: Depending on the species Walnut trees grow to be around 33 to 131 feet tall.

Bark: Their bark may vary between species. The Black Walnut has a bark that is dark brown to grayish black and deeply furrowed, forming a diamond shaped pattern. The English Walnut bark is a silvery-grey, especially when it is a young tree.

Fruit: Walnut trees produce a round, single-seeded fruit called a ‘walnut’. After it is ripe the husk is removed, revealing the wrinkly walnut shell. Inside the shell is the meat of the nut, which can be eaten raw, candied, roasted, pickled, or as a part of a recipe.

Common varieties of Walnut trees used for firewood

There are around 20 different types of Walnut trees, but only two are commonly grown and harvested in the United States.

Black Walnut is one of the best known and valuable trees because it produces tasty nuts and beautiful lumber. It is found primarily over the eastern United States and as far west as Nebraska, Kansas and Texas. They are not really cultivated on the same scale of English walnuts. It prefers a deep, rich, moist but well-drained soil. Black Walnuts have a bold, earthy flavor. Their shells are thick, tough to crack and will likely stain your hands.

English Walnut/Persian Walnut produces nuts that are easier to process and have a more pleasant mild flavor than the nuts of the Black Walnut. They are grown widely in California. The English Walnut grows rapidly and can reach 40 to 50 feet tall and lives about 60 years.

Working with Walnut Firewood

What does Walnut smell like?

One of the best things about heating your house with firewood is the aroma that comes from the wood. Walnut firewood has a very pleasant smell.

Many people like the smell of Black Birch which is also known for having a pleasant wintergreen smell unlike Cottonwood that smells like cat pee when burned. Yuck!

Is Walnut sap messy?

Walnut trees are pretty clean especially when compared to Pine trees. Prepare ahead of time when cutting Pine! The sap will get all over your gloves, work clothes, shoes, and chain saw. Maple is clean when matched up to Pine.

Home owners complain about the mess and annoyance of walnuts landing on their car. My suggestion would be not to park under a Walnut tree.

How hard is Walnut to split?

Walnut trees split very easily unless the tree is forked and knotty. Sometimes Walnut trees that have been grown for landscape purposes will not have straight grains.

If you can choose, it’s best to find Walnut trees that are coming from a stand of trees, which will cause them to grow straight and tall, and produce a better wood than one that is out in the open, like a yard tree, where it will grow a large canopy.

How long does Walnut take to season?

Hardwoods, like Walnut, are denser and burn hotter and longer than softwoods, but you’ll need to let them season for around a year, after being split, to allow the moisture content to reduce.

For optimal burning, firewood should be dried until its moisture content is less than 20 percent. Firewood with a moisture content higher than that may eventually burn, but it is difficult to light and hard to keep burning.

Buy an inexpensive easy to use moisture meter like this one, to ensure your split wood is ready for the fire.

Does Walnut burn clean?

Walnut burns really clean when it is properly seasoned. Some people complain that Walnut firewood leaves a lot of ash behind. Walnut is a hardwood, but it doesn’t burn for very long when compared to Oak or Pine. If you can mix your Walnut firewood with one of those two, you will have a great fire going!

Heat Output and Efficiency of Walnut

Depending on the species, Walnut produces anywhere from 20.0 to 22.2 million BTUs per cord.

On average a cord of Walnut is equal approximately to the following common heat sources:

• 20,347 cubic feet of natural gas.
• 231 gallons of propane.
• 152 gallons of heating oil.
• 6,184 kilowatt hours of electricity.

BTU stands for British Thermal Unit. One BTU the amount of energy required to heat one pound of liquid water by one degree Fahrenheit.

A cord of firewood is equal to 128 cubic feet of wood. Typically firewood is cut into 16 inch lengths and is tightly stacked in three rows, 4 feet high and 8 feet long, totaling 128 cubic feet.

How does Walnut compare to other types of firewood?

Walnut is a good firewood when compared to other firewoods because of its medium density and ease of burning. It burns clean, is easy to start and has a pleasant aroma. Walnut may not produce quite as much heat when compared to other hardwoods such as Oak, but it is much better than burning a softwood such as Cedar.

Walnut falls somewhere in the middle in terms of BTUs per cord. At the high end would be Eucalyptus at 34.5 million BTUs per cord and Osage-Orange at 32.9 million. On the low end you have Ohio Buckeye at 12.1 million BTUs per cord and Linden Basswood burning at 13.8 million.

Fire quality, amount of smoke and creosote.

Walnut firewood tends to burn very clean without a lot of smoke or sparks.

Green wood tends to smoke and smolder creating the possibility for creosote to form in the chimney. Creosote is nothing more than a condensation of small, unburned particles contained in the smoke that coats the chimney surface as it exits. The creosote will stick to the sides of the chimney and can ignite, causing a chimney fire.

All wood creates creosote. Hardwoods, like Walnut, burn slower and lower, so the smoke lingers longer inside the chimney, creating more opportunity for creosote build up. You can reduce the amount of creosote by properly seasoning your Walnut before burning.

The Pros and Cons of Burning Walnut as Firewood

Pros

• Has a very pleasant scent.
• Produces good heat and burns clean with little or no smoke.

Cons

• Walnut trees produce a toxin that effects other plants around it.
• Isn’t readily available all across the United States.

Other Common Uses

Walnut plays a major role in furniture because of its attractive timber, which is hard, dense, tight-grained and polishes to a smooth finish. Generally, Walnut wood is the highest priced domestic hardwood because it is such a quality lumber. Walnut furniture can easily last a lifetime.

Many people love to eat walnuts because they contain good fats, iron and taste great!

There are many different firewood species to choose from. However, not all of the options will be available to you since some trees only grow in certain parts of the country. In my opinion, Walnut is a great choice for firewood because it produces a good amount of heat and burns clean.

Tell me what your favorite type of firewood is in the comments below.