a CL ad that leaves with a warm feeling, not (?)

Ulmas Glabra 'Camperdownii'.... weeping elm for the regular folk, from the looks of it.
That tree in it's current size would run $1,000 - $1,500 at a nursery EASY, problem with that one is a lot of the feeder roots maybe under the driveway on that side of the tree.. also looks planted too deep but it's hard to tell. the man is correct it is planted way to close getting it out now will give the best chance to save it.
going to have to find someone who really want's it.. those roots go a bit beyond the edge of the tree and probably 4-5 foot deep, always think the roots size mirror the tree above it.
good luck... personally I'd dig it up and move it somewhere else on the property, those are very majestic tree's with another 30 years of growth.

I have seen a few in the area but it's very much pushing the cold limit of the tree where I am. That was "nursery price" it looks as he know's it's worth some decent money to the right person as he is requesting a tree spade.

not sure the cost for that machine in your area, personally that would be small enough to consider hand digging myself.
@ white walnut as there reffered to here
tree's grow the fastest where they get what they need as far as sun, water, nutrients and climate/ micro climate... some are slow growers some are fast... can't say for sure what's up with yours unless I see it, I would expect to see 4-6 in of new growth yearly on the branches and main stalk height and maybe 1/16- 1/8 in per year on girth after the first 2 years. as you want root growth the first 2 years after planting, more than plant growth.
if you compost toss some around it every spring (maybe a very light fertilizer 3-4-3 and sparsely at that if you don't water regularly) and give them a little water during the dry times as they are still small, and possibly struggling to establish a good root system (one of many many possibilites)
pruning also helps slow growers produce fresh growth and speed up but not always needed once again it's a gotta be there to see if it can be worth while.
still I would expect nuts from an 18" starter in about 9-10 years maybe earlier if conditions were perfect
I could ramble on all day lol....

talked about white walnuts at work today with quite a few people and learned a few things that may help.
They are slow growing tree's, they are generally an undergrowth tree and are commonly found on or near riverbanks naturally. your soil sounds fine, they should produce in 5-7 years not 9-10.. water water water