Your plant is not likely anything all that special. The way to find out is to make sure its roots are right, plant it in the ground, and observe it for 10 years. I feel that it's been stunted by a life in a pot. If the tree in the picture is a selected cultivar, there's nothing remarkable about it and isn't worthy of special naming.

It's probably a bit slower than a plant growing under ideal conditions in its native range, but not by much. What's going on under the soil? Planted too deep ... on a clay pan? Girdled roots? I fully believe that most woody plants in cultivation die within a couple of decades because of root issues.

Your trying to make an observation way too soon in tree time. Many of the plants I purchased in fall of 2014 are just hitting full stride now, 4 years later. This year my Gold Drift probably put on a foot of growth, and it had never come close to that in years past, same with many of the other early plants I purchased. It takes time and conditions must be right for them to grow. My Picea engelmannii 'Bush's Lace' doesn't come close to matching the growth rate, because it's miserable here. I have Chamaecyparis nootkatensis 'Jubilee' planted in 2013, but it's in shade, and although it looks healthy, if I showed you the first pic I took of it 5 years ago, there is almost no change in size. This is a plant that is supposed to grow 15+ inches a year.

It sounds like you've really made up your mind here ...

Those 150-footers in Japanese forests. How long did it take them to get that big? 300 years? Longer?

Those terminals on the big tree in your opening dialog seem to be increasing at a rate of 8 inches / year. Plus the trunk width seems a little narrow for something 60 years old.

After 12 years in a pot, there's probably not much nutrition going on in there.

"The parent tree was grafted itself as well."

Folks don't usually graft a species, so it may be a known cultivar whose identity is now forgotten, but I must admit, I agree with Dave. Who planted the tree and how do you know it is grafted?

tj

So you think the specified age of this tree might be incorrect? I actually don't have a valid reason to completely believe what the grower told me. He told me its been moved around a lot and its been in that particular spot for 40 years but about 60 years old in general.

And he grafts it because its impossible to grow from cuttings and he doesn't propagate from seed. Grafting is his main method of propagating. And seed growing isn't the most reliable either. The guy told me he planted it 40 years ago and I'm not sure if I completely remember this but I think he said his dad grafted it.

What if it’s simply Howell’s Dwarf?

I thought Howard's dwarf starts off with a spreading habit. My potted grafted trees that came from this tree are upright.