Lots of rumors about how black locust is allelopathic but, anecdotally everyone seems to think that they are good. I read this study:
which seems to conclude that it is not an issue but I was wondering if anyone has seen any good sources which claim that black locusts can be a big problem.
I had to remove five of them this winter. They grow straight up about 60 feet and then the trunks get hollow as they age. It they are near structures they are danger in storms. Because of their height I had to hire professionals to do the job. Allelopathic? I’m having trouble getting grass to grow where they were.
This is weird. It’s almost the exact opposite of my experience.
We have a sawmill and a bunch of large black locust trees on our property. They make fantastic boards and I’ve never noticed them to be hollow.
Our soil is super depleted to the point where grass doesn’t even grow in most of it. The only place that grass grows around our place is underneath the black locust trees.
It’s almost like we’re talking about different types of trees! I know one of the studies mentions that and might depend on if they are native to your area because some plants are allelopathic in some places but not in their native environment.
The best firewood out there more BTU’s per cord than any type of oak. I just cut down a 50 foot Honey Locust and the rounds are a month old and still so hard I can’t split them by hand. I’m going to give it another month to dry. The wedge will not go into the wood.
No hollow spots in this tree either just dense beautiful looking wood.
The grass is probably due to their nitrogen fixing ability. I hear the honey from their flowers is quite good too. It’s considered invasive in a lot of places, but seems to me like a super useful tree all around. I’m gonna cut some tree of heaven (which is invasive and allelopathic) growing on my property in the fall, hit the stumps with some triclopyr and plant some black locust seedlings I’m starting this year in that spot next spring.
Black locusts on my old place in Dane County, WI would often have hollow trunks. Black locusts on my folks’ old place in Juneau County, WI (about 75 miles north) rarely if ever had hollow trunks. I always assumed soil had something to do with that.
I hated them at both sites. I would never plant a black locust.
i would if i want them for timber or firewood. once cut they just reseed themselves. our poplar here does the same but black locust is far superior than poplar for both timber and firewood and from what ive read grows almost as fast. i see it a a viable option to produce quality firewood in 1/3 the time you could grow a sugar maple or beech which is our best burning firewood here. red oak would be another id grow with it. both are excellent for wildlife as well.
If poplar is your only other choice, then I’m sure black locust would be welcome. They grow much, much faster sugar maple or red oak.
They not only spread by seed, but they also spread by suckering. There were nearly one acre stands of pure black locust on and near my old place. Nothing but grass and a few wild black raspberries grew under them.
They are pretty and smell great when in bloom. That’s about all the nice things I can say about them
Black locust do seem to ‘discourage’ competing trees.
We had a stand of black locust on the orchard property. They weren’t even good for fence posts, chronically diseased, rotten and crooked. They are still coming up 3 years after removal, spreading by root and popping up 30 yards from where the stand was. I expect we’ll never be free of them, they’ll be a constant maintenance issue among the trees along the road. Now they’ve crossed the road to an unmaintained property where they’ll become more of a nuisance.
They probably out compete some things, but oaks eventually overtake them, and I imagine other species do too…but having planted black locust intentionally over 35 or 40 years, actually longer back than that, I have observed they don’t ‘invade’ timbered areas…but are a great erosion control, make super honey, and even make a half-decent shade tree if you keep the root sprouts cut to the ground regularly. Like ginkgo or gum, grass lives under black locust just fine. Plus the posts/logs last longer than treated CROSSTIES.
Some locust I planted about 1991 or about time I planted some M7 apple trees, have all died…being out-competed by oaks. Locust makes great strip mine reclamation trees.
(OOoops, anyone under 40 may not ever have even seen a ‘strip-mine’…they may think it’s referring to removing clothing or something…lol ).
Someone on another board says he loves making outdoor furniture with locust because of its longevity outdoors. Also amazing firewood tree. Around here a lot of street trees are honey locust. Isn’t the issue the thorns?
Honey locusts in nature have some ferocious thorns…being the barefoot boy carrying a rifle on the shoulder…I’ve stepped on some of those thorns back in the day.
The cloned/grafted honey locusts in parking lots and along streets don’t have the thorns, but most native seedlings do. Honey locust do not rot quickly, but don’t
have longevity of black locust.
Ok…i was wondering why i never notice the thorns on the city trees. I figure it was due to being mature trees. Seedling pears have nasty thorns as do citrus.
With ash borers, elm disease, oak diseases, chestnut blight… running out of hardwoods!
Black Locust is a favored silvopasture tree because other things, grass specifically, grow well in their dappled shade. I’m actually planning on putting some in this year for that reason.
In terms of firewood, it’s pretty decent. Not as good as Osage Orange but comparable to mulberry.
Same concept. A thousand pear seedlings and you find a pretty one that has no thorns…you patent it and graft millions and sell them. That’s Bradford’s claim to fame.
Osage doesn’t grow here, but i’m trying a few anyways. Up here red oak seems to be the most common firewood. I collected both honey and black locust seeds this fall…going to sprout them here shortly (been in refrigerator for months). I’ll grow them out in pots.
The main problem I have had with black locust is they are prone to topple in storms. The wood is super heavy and when the soil is saturated and wind comes they fall over. No noticeable problems with allelopathy though, and we used to have three big ones.
I felt guilty chopping one down recently and not keeping the wood, but we already have way too much firewood from past tree removals.
Not sure if Osage can handle your cold…but you can lime the soil to encourage it to thrive.
Allelopathy is one of those things that science is learning more about all the time. Years ago we would just talk about walnut being allelopathic, yet there are so many plants that are known to be allelopathic I never see it as a bad thing if a tree or plant is allelopathic, I try to learn and observe as much as possible about the allelopathic plant in question.
Here is a list of trees that are know to be allelopathic. (my guess is that to some extent all plants use allelopathy to give themselves some advantage.)