Burning Black Walnut

We were in Seattle on vacation when I got the call. A summer storm, a series of microbursts, and the 100 year old black walnut tree in our back yard was uprooted and fell on our tenants’ roof. It was still raining in Massachusetts, so I called the tenant and my stepson and the two of them managed to spread some blue tarps over part of the roof.

The next day, Friday, I got some pictures. The front of their house was completely framed in green. The backyard was filled with trunk and branches. I called a local tree service which dispatched a crew to get the roof cleared. The insurance company sent out an adjuster and a clean-up company who got the roof covered. Once they could look at the roof, the damage was limited to a large hole over one bedroom. Fortunately, the house was still livable. We flew home on Sunday.

I talked with the tree service crew to give my OK to cut back some bushes so they could get access to the backyard. “Black walnut,” the crew boss said. “They use that for gun stocks and furniture. Worth a fortune. It’ll probably pay for the cleanup.”

The tree guy I called that Monday was less enthusiastic. “Yeah, I took down a black walnut a couple of years ago and I heard the same thing. No one wanted it. I ended up selling the trunk for $500.” Still, he agreed to leave the main trunk whole while I shopped the tree.

Two sawmills I called had the same response. “We don’t take backyard trees. Nails. Who knows what. Our blades cost $1500 each.” I offered to pay for a new blade if it was needed, but got the same response. I ended up selling the trunk to a local woodworker for $500 and the promise of a bowl from the wood in a year or two. He left a lot of scrap that I figured I would burn. It took me until October to cut and split the scrap and I had close to three cords when I was done. We go through that much in a winter, so I figured I was set for a year. With the insurance, the $500 and the savings on the wood, we probably made some money, if you don’t add in the time I spent splitting and stacking and dealing with the insurance and roofers.

There are a lot of black walnuts in the area. The B&B at the end of our street is named for them. The nuts are edible, or so I’m told. They are encased in thick green hulls and once you get inside, the meat gives off a serious black stain so I never really tried it. I’ve seen some black walnut cookie recipes, but it seems to be one of those local foods that people used to eat because it was available.

So, aside from finding squirrels’ stashes of walnuts in our woodpile, I paid little attention. Friends who have horses always noticed it—black walnuts are bad for horses. My wife had me move our compost from under it because black walnuts put out a chemical, juglone, that discourages other plants and she was convinced our compost was picking it up and killing her flowers.

No one I knew had ever burned black walnut, but it was a hardwood and a year old by the time I got to it. According to some websites I found, it has a pleasant smell, is hard to start, and doesn’t burn as well as maple or oak. I’m here to tell you differently.

First, it is a bear to start. We end up each summer season with garbage cans full of kindling. In order to start the walnut, you need a lot of kindling, almost half of the small Jotel full. I don’t find the smell pleasant– it smells mildly toxic to me. It’s the olfactory equivalent of juglone—the smell of it will definitely discourage someone from burning the wood.

Once you get it going, it quickly overheats the stove, sending the chimney thermometer into the red. When you turn it down, the chimney smoke gets darker and sootier. It takes a lot of fine tuning to make it work. For all of that, it doesn’t burn as hot as maple, birch, or oak, the woods we most commonly burn. It takes a while to heat up the kitchen and the brick chimney, during which my wife complains that the kitchen is still cold.

To its credit, black walnut coals burn forever. The next morning, what looks like white ash turns out to have dozens of small coals in it that continue to burn and smell in the ash bucket. Invariably, I ended up taking it outside to let them die out in the open air. And the ash. Sherlock Holmes was able to recognize over 150 cigar and cigarette ashes at a glance. I’m not that good, but I can tell black walnut ash at 20 paces. Pure white, fluffy ash and a lot of it. Normally, the ash bucket will go for nearly a month before I need to empty it. Black walnut ash fills it in two weeks. And be careful where you dump it. It’s almost definite that there are live coals in it.

It lasted from October to the middle of January. I’m burning maple, now, and it is amazing at how little it takes to start it and how well it heats the room. My neighbor has a black walnut that’s leaning over our property that I view with more than a little dread. Last thing in the world I want is more black walnut.


Burning Black Walnut — 8 Comments

  1. No idea. I put the ashes outside in a place where a lot of bushes grow with no ill effects. That’s all I know.

  2. Don, Black walnuts are delicious. They have a different taste than the milder English Walnuts; one might even say an acquired taste. If so, I have acquired the taste, I love then. I used to collect my own. Stomp off the green husk and let them dry for 3 or 4 months. They are almost impossible to crack and obtain the nut inside, but worth the effort. Now I buy them off of the internet, 10 lbs at a time. If you get a chance, give them a try.

  3. Not yet. I get the feeling it will take another year for him to get it all together.

  4. Don, Interesting! How little I knew about a tree in our backyard. Our compost pile is also under a black walnut tree but I never thought about its impact. Those nut casings are quite a mess once they start to rot. — Jan W.

Leave a Reply

Your email address will not be published. Required fields are marked *