With Oikostreecrops offering hybrids (some are almost all American) that most likely won't get diseased, why not go w/one or more of those? I have a Timburr that's 12 yrs old. You'll need more than one for cross-pollination to produce nuts. Below is the link:

https://oikostreecrops.com/products/?route=product/category&path=63_88

As noted above...loosen the native soil and plant. Do not amend the soil. That you are growing (without chlorosis?) Sweetgum and Blackgum in native soil suggests the pH will be low enough for Chestnut.

Chestnuts are pretty bulletproof. Make sure the soil is not alkaline, although I have even seen them growing in limestone soil. Make sure there is good drainage! They don't like flooding, and you never know you might encourage phytothera infection. Plant in as much sun as possible. They can survive partial shade but growth is massively stunted.

I wouldn't worry about getting big ones - they grow FAST - I got 2-4 feet per year in Minnesota, you will probably do better once yours get established. Big ones are harder to transplant, and if you don't have tall pots your taproot starts bending around.

Concur with previous posters - you don't need to amend the soil... chestnuts are often planted in harsh soils for reclamation. I do like to hit them in the spring with some fertilizer, but it is not necessary. You may want to protect with cages if you have problems with voles or deer or anything like that.

I have noticed they need a year or 3 to kind of get established, and then they throw up a 3 or so foot leader once established.

Corkball, how did your trees do in Minnesota, I am getting a few this spring.

They were super solid. But keep in mind, I was in the Twin Cities in south suburbs, so that is like 4b. If you are up on the range I wouldn't count on it working out too well. If it was a really bad winter, I might get tip dieback, but never really had any hardiness issues. That applied to American, Chinese, and hybrids. Did not try Japanese or European since resistance to blight isn't supposed to be all that great.

Thanks

I live on PEI, quite a bit north of you, so take that into account. Chestnuts like sour soil, lower pH, and they don't want amendments in the planting hole. Dig a deep hole, place the tree at the same height it was when you got it, roots as deep as they were before it was dug up. Water after planting, water if it's very dry, that's it. They grow underground at first, so not much top growth the first few years. Once the roots are large enough, and the reserves stored in them are plentiful, stand back and enjoy the 3 to 4 feet of top growth they produce each year. We have some in our woods that I planted from nuts in 2006, and they are over 20 feet now. Even lawn trees grow fast, although not as fast as the ones in the shelter of a woods clearing. Enjoy :)

Thanks to all of you for responding.

I'm torn between my experiences and the info you knowledgeable folks are telling me about not amending the soil.

I want to explain why I usually add amendments, which you folks are telling me not to do.

The existing soil is clay. I use a pickaxe to break up the soil, and then a shovel to remove the clumps. As I dig deeper, when there's no room to use the pickaxe, I use a hammer and stone chisel. There are no roots to contend with. Although some sections of my property is somewhat wooded, the sections where I want to plant have no roots extending from existing plants. There are no earthworms. In the past, when I didn't amend the soil, plants either died or their growth was stunted. Presumably the lack of growth was because the clay packs down quickly. However, please note that the soil does seem to percolate. So I figured that the roots aren't strong enough to penetrate that mess and the roots needed something less dense in which to grow.

The website that sells the chestnut seedlings said to add compost or peat (I understand acidifying soil, if needed).

If my explanation comes across as snarky, I apologize; there was no intent. But I hope you understand my dilemma.

You could add a little sand. If it percolates though, you might not need the sand. Mulch on top of the soil would work well to add nutrients and the worms will take it down into the soil. If you add amendments to very clay soil, like ours, the roots just circle around like a pot, and don't grow out. After a bit, the tree lags as it has not grown out into the native soil.

A lot of trees grow fine in clay but do take some time to get settled in, I am not sure on Chestnuts but will be doing the same, my problem will be hardiness. Clay has the bonus of holding moisture longer and has minerals .

The property is on a ridge in which there are varying degrees of slope. That means, here, topsoil and leaf litter wash away to other parts. That's where existing trees have grown.

I intend to plant four seedlings: one in a deep pot in potting mix as a backup, one with no amendments in relatively good soil, one with no amendments in clay, and one with amendments in the top third (eight inches) of clay. I'll probably be dead before I can review growth.

Thanks again.

Well, maybe not, grin. 10 years will tell you a lot. :)

Over the years, a number of tests have been done about amendments added to backfill soil when planting trees. These tests have been conducted in all types of soils including clay. In some circumstances, initial results can appear promising, but tests consistently show that amendments are contraindicated in the long run. Suggestions above agree with those test results. If you just want to tinker, that's understandable, but, if you really want to give your trees the best chance, there's no need to "reinvent the wheel". Amendments can interfere with drainage and result in a poorly formed root system.

Adding a little sand to clay (as mentioned above) does not improve drainage at all. It would take a large percentage of sand in a sand/clay mixture to improve drainage. There are great explanations of why available with a quick Google search. Adding an organic mulch as a top dressing is a very good idea and can help in multiple ways (eventually improves soil texture, holds in moisture, etc).

You asked about using 8"-12" seedlings versus larger trees. The smaller size trees will work great IF you can protect them from predation and keep them properly watered for at least the first year. Smaller stock is easier to plant and, if properly planted, has a better chance to develop a very good root structure best adapted to the planting site. It's not unusual for smaller trees to catch up to or surpass larger specimens in just a few yeas. While 8"-12" trees should do great (if properly protected/maintained), a little larger plants might be better, especially for remote sites where you can't baby your babies.

Here's some links you might find helpful:

Planting a Tree or Shrub: sites.google.com/site/tnarboretum/Home/planting-a-tree-or-shrub

American Chestnut Cooperators' Foundation (going about it differently than the American Chestnut Foundation): accf-online.org/

Sometimes what you put in the planting hole is about making the owner feel better, grin.

Assuming the owner is not elderly, he will have many decades to continue to plant. He'll learn as he goes.