Thornless Honey Locust -Grafted?

[CreakyGardener]

I grew up with Locust trees, remembering them fondly, except the thorns that found their way into things once in a while. I recently found a Thornless (Imperial if memory serves) variety at a local big box store and they all looked grafted at the bottom. The Locust Trees in my area are all old and healthy, so I think it's a good choice for our yard, as we're looking for the right trees to plant.

My concern is what they could be grafted onto? I couldn't get an answer from the nursery the tag was on, so I gave up. The reason I'm curious is because I'm in Oregon - the Northwest, in our area we have a high water table in winter and it gets dry/lower in summer. (I do water our trees in summer to avoid stress.) Locusts that I've been around, were hardy in the driest of places as well as around ponds and marshes too. I was concerned if I got a tree grafted onto something else that they may not thrive as equally?

The only reason I can imagine they'd do that is for a less invasive root system so they can be planted in the city near sidewalks and streets? I really don't know - just an assumption. Every one of them had a wound at the base that looked like a second lead cut off and a bit of a bulge in that area as well as a bright green spray paint line,... perhaps a suggested planting debt or tagging system? I was hoping some one might have some ideas if it sounds grafted, what they may've grafted it to or any thoughts to share?

I do have other questions about this tree, but I'll put those in a separate thread since it's not part of this.

Thanks for reading and hope all is well!

 

[Marck]

This thornless and fruitless cultivar of Honey-locust (Gleditsia triacanthos var. inermis 'Imperial') will be grafted onto a seedling of Honey-locust that will most likely be thornier than the selected cultivar. This is done because it is easier to vegetatively propagate a honey-locust cv. by grafting than by other methods such as cuttings or tissue propagation. This shouldn't be a problem as long as you prune off any suckers that emerge from below the graft union. Also the tree should be planted at the same level that it is growing in the pot. I do not recommend burying the graft union.

 

[CreakyGardener]

That's great news, Thank You! Yes,.. very good advice for planting too. I've unfortunately learned the hard way - and a few reminders along the way - to be aware of planting debt and not digging a hole that sinks or settles later - lowering the tree and allowing dirt to gradually level out as if it was buried too low. Thanks for the help!