Question
Due to a borer insect killing off the black locust trees here in Oregon, we are able to acquire a large amount of locust logs. I would like any information on the marketability of this wood and what it might be used for.
Forum Responses
Black locust is not native to the West Coast, so make sure that it is the same species that we call black locust in the East.
It is the hardest commercial species in the U.S. That certainly means hard to saw, glue, machine, etc.
The main use today for black locust is... xylophone keys!
If used for firewood, it is exciting--the moisture in the wood is converted to steam during heating, but cannot escape. So all of a sudden, "POW!" and then sparks fly all over.
Gene Wengert, forum technical advisor
The trees I have tend to be gnarly and the larger trees decayed in the middle. It would be very difficult to get much lumber out of a tree.
Comment from contributor A:
I am a wood flooring contractor and have installed a couple black locust floors. I take exception to a comment above to the effect that it is low grade.
Not only is it tough (second only to osage orange as the toughest native wood) and resistant to moisture (much better than white oak) and rot (way batter than cedar), it is gorgeous! If you haven't seen it, picture the grain of oak and color it with gold and add a glow that shifts in the light.
Black locust is tougher than hickory, which is tougher than hard maple, which is tougher than oak. I have gotten it for only slightly more than the price of oak.
I only wish there was a supply of the lumber in my area. I'd make everything out of it. It has a very low rate of expansion and contraction, making it very stable for furniture and woodwork (interior or exterior).
Hard to work? Well, it's not balsa. Whaddaya expect when it's practically the most durable and stable wood available? Use sharper tools.
It's great for furniture, ideal for boat building and decks. It's also great for fenceposts, but that's a waste of a wood that is our best wood. It's a native exotic.
It is native to the Eastern USA, but was brought to CA by goldminers to grow for minining timbers. The railroads also planted it because it makes excellent railroad timbers for bridges and railroad ties.
Black locust can last well in excess of 70 years in the ground without painting or chemical treatment. It's very strong, shock resistant, stable (doesn't shrink or swell much), durable (rot resistant), looks great (in part due to fluorescent grain. It's somewhat hard to work, but not too bad, considering it's very hard. It's easy to glue. Unlike other very hard woods, black locust nails reasonably well. It is also a fairly smooth wood.
To get better physical properties than black locust, you have to look at ebony or some other expensive, exotic import. You can basically think of black locust as hickory that is more rot resistant and more stable when humidity changes. It looks similar to red and white oak, except is better looking due to greater smoothness and fluorescent grain.
It's considered a pest by some Western environmentalists because it's an aggressive tree that kills the Western native trees and plants in a wide area around it. However, that was a very useful quality to pioneer farmers who worked hard to clear fields. The easy way to keep a field cleared of brush, alder, other trees, and weeds is to plant some black locust. Black locust only allows grass to grow in its field. Nothing else. That's a convienent way to keep a field cleared without manual weeding or spraying weed killers.
Black locust is mostly dead in Oregon now due to a beetle attack. Black locust is mostly ignored in CA and WA. Though native to the Eastern USA, it's spread all over the Western USA and parts of the Southern Midwest and Europe. It is appreciated by environmentalists in those places because it is an easy, quick way to reforest strip mined areas and logged out areas. Although it prefers good soil and lots of sun, it can grown in bad soil (mine spoils) and cloudy and cold climates too. It has spread all over Canada over the last 250 years.
It was imported to France in the 1600s. The French recognized awesome shipbuilding wood when the saw it. They also used it for medicinal properties (seeds) and cooking (flowers). The seeds have also been used in Europe as a coffee substitute. The English importanted it to England hundreds of years ago where it still grows.
It has spread all over Western and especially Eastern Europe. The Europeans appreciate the black locust for it's supposed medicinal properties (seeds are laxative) and for the quality of its wood. The biggest attraction is that it is an aggressive tree that self-cultivates and spreads without any human effort needed. The black locust is reforesting much of the logged out areas of Europe that have been logged out for centuries. It's also a renewable resource for them since it's so easy to regrow. It's such an aggressive, persistant tree that it continually replants itself. Black locust is the national tree of Hungary and the basis of their forestry industry.
It makes great fence posts, but it's a far superior wood to white oak, hickory, hard maple, walnut, or cherry for furniture and boat building. Using black locust for fence posts is not the highest or best use of this wood. Black locust fence posts last well over 70 years without needing any chemical treatment.
I found a supplier of it who sells it for a bit less than white oak. I'd like to build a house and use it for the hardwood floor and desk. It would probably make great siding and roofing, too. Since it lasts 70+ years in the ground, it ought to last hundreds of years as siding or roofing. It's supposed to nail reasonably well.
These are both native exotics. Exotic because they aren't widely used or known. The physical properties of black locust are nearly identical to purpleheart. The physical properties of osage orange are nearly identical to santos mahogany (not mahogany). The properties of black locust and osage orange are similar to hickory, except that hickory isn't very stable (shrinks and swells a lot with moisture changes and can rot easily if used outdoors). Both black locust and osage orange have the same good properties as hickory without its bad properties. Black locust and osage orange are stable and resistant to rot, mildew, germs, and bugs.
Don't whine about hardwoods being hard to work. What would you expect? If you want an easy-to-work wood, use a softwood, but expect dents and dings in the furniture or whatever you make from it. Hardwoods are tough, so they resist dents and dings. Therefore they also resist tools when working the wood. Use sharper tools. Use carbide tipped tools whenever possible.
It is also highly invasive, and while a controlled stand might be something very useful, it is good to remember that the stand will take over everything else if left untended.
Years ago a friend who does permaculture design recommended using existing stands for whatever I needed, but never to plant it. It regenerates itself quickly.
It may also be toxic to children, who love things that look like beans. Like poison ivy, the levels of toxins may vary at different times of the year and in different parts of the plant.
Be careful; don't plant it unless you can also be sure of removal if necessary.
Green-cured black locust, or fresh cut, is not terribly difficult to work with as the wood gives way to sharp implements and is fairly easily worked. Long, or "weather-cured" locust, locust that has been slow cured by age often in areas exposed to weather, is very hard and very difficult to work. In fact, if you try to cut an old locust fence post with a chain saw, a six-inch log will dull a brand-new chain, and forget about hand-planing. It's almost impossible to even drive a stout spike into a well-cured log unless you use very hard (and brittle) masonry nails. Everything else will pierce only about an inch and then bend. If you intend to work with black locust, make sure it hasn’t been too-well cured. If it has, you'll only make much progress with power planers, high-grade saws and high-pressure nail-guns.
For use as flooring, trim, or projects it will need to be fully dry. With a good flooring stapler, you can nail the flooring down, but plan on drilling trim or projects before nailing. The wood that isn't good enough to be used visibly can be used for framing in high moisture environments, such as pool rooms, kilns or saunas. Otherwise, it is good for pallet stock or various small items. Below is a list of things we have used it for and the degree of success we achieved.
2x4, 2x6, and 2x8 framing timbers - excellent if you use decent lumber and don't wait too long.
Tongue and groove flooring - we put it down too soon and it shrunk. It is very hard and does the job, if you like yellow/green floors.
Exterior log posts and rails (8" plus diameter) – it has worked well so far. Very sturdy, no rot so far (only 3 years) and decent appearance with proper log selection. The stain we used didn't stick very well. It seems to have to do with the oils in the wood.
Bed frame struts - excellent, very sturdy and effective.
Three mowing machine pittman arms - fair. The first two broke because the grain was so uneven. The third one is still holding. Had we selected a piece with continuous grain from end to end (hard to find) it would probably have worked better.
Wheelbarrow handles - excellent. They were a bit hard to turn due to the hardness and open grain. It tends to grab the tool a bit, particularly on long work pieces like wheelbarrow handles. They are very strong (it's a large wheelbarrow and I've been using it a lot) and should last a long time.
The downside to this tree is that it's not the best choice for a yard. Its shallow surface roots make it prone to uprooting under certain weather conditions. Overall it's a very valuable wood with many uses and one of my personal favorites for firewood. Additionally, its rapid growth rate makes it a renewable resource - something we all need a bit more of!
Let me tell you, once properly split and dried, that wood is among the best I have ever burned in my heatilator-equipped fireplace. It burns slowly, and very hot. The key mechanism here is to make sure it is properly stacked and dried; this will keep spitting during burning to a low level. While splitting the wood one can't help but notice a beautiful gold-green sheen to the heavy, straight veined splits. The wood is as hard as any I've ever worked with, and I must agree with the wood-working individual above who states that it is of the highest quality!
After reading your posts the original plan to let the tree crew haul it away will change to having it band sawed into boards by a local guy with a portable mill. I could use some new decking and it sounds like the way to go! Thanks all for your comments - and I agree with the burning of it. Once it’s dry it gets the wood stove hotter than any other wood species.
On a job a couple years ago I found an old split rail in the dirt on the dark side of the building. I picked it up and was amazed at how heavy it was. I cut it in half and the wood was obviously locust and looked as good as the day it was cut. We harvested some logs from a stand next to the project and slabbed some planks for mud sills. I've started about two thousand seedlings and am seriously considering expanding my business to deal in this amazing wood.
