I just planted four Chestnut trees, two Chinese chestnuts and two Colossal Chestnuts. They are seedlings, only about 16 inches tall.
I live in central Kentucky, zone 6b. Summers are fairly hot and humid.
What problems should I expect? And spraying or care that I should definately give them?
Any advice would be greatly appreciated.
John in Kentucky
Chestnuts have been zero issue for me in my hot humid climate. They are almost a set it and forget it.
Don’t let them die without water in the middle of summer for a couple years!
Maybe paint the trunks white with 50/50 low VOC interior latex paint and water to prevent sunburn and springtime cracking.
Also stop bucks from rubbing them, and get BT spray (bacteria pesticide, not chemical at at least) if you have tent caterpillars.
Have read not to plant colossal near Chinese varieties due to causing internal kernel breakdown.
I add a little horticultural mulch around my american trees each spring and that’s about it. They’re growing like weeds. I’ll enjoy them until the blight inevitably cuts their life short.
The european nuts pollinated with chinese pollen can rot, that’s true, you may loose 1/3 of the european crop.
Get some Dunstans! They’re a good American strain and 1/8 Chinese.
Also Japanese chestnuts and Chinese chinkapin are analogous trees to the original American chestnut, both available in the US now.
Nah. I’m all about bringing the American tree back with near 100% genes. I don’t believe the Dunstan has that much American in it either…it has a lot of Chinese to have that much blight resistance.
The SUNY ESF Darling 58 American chestnut seems to be the best route to bring back castanea dentata. They only had to alter 1 gene out of about 40,000 to give it the blight resistance. It just needs the federal approval now. I’m not a huge gmo guy, but in the right situations I’m okay with it and this is one of those examples.
Thank you everyone for taking the time to write and for your feedback.
Glad to hear that they don’t need to much extra care or have many enemies. I will hit them with BT periodically for any cateripillars around.
The nursery I bought my two varieties from told me I need two different kinds for the best polination, hence getting Chinese and Colossal. These both came to me from seedlings, not grafted.
Are you sure the two won’t do well together? The little research I did seems to show that Colossal is a mix of a European Chestnut and a Japanese chestnut.
I would also be glad to get a pure Japanese chestnut if I can find one. Do they also have issues with Chinese?
I am mostly interested in growing them for the fruit, and for a tree that will last and not get knocked out by blight.
John in Kentucky
1 gene plus destroy the plants resistance to mutation so that the modification will stay.
That’s how they do the GMO’s.
Why isn’t the Dunstan Chestnut 7/8 American, good enough?
And if not, why not find another blight resistant American chestnut (it seems there are at last 3 in the US) and cross it to get it to 15/16 American, or more?
In my opinion GMO’s are a weapon as dangerous as leaky nuclear power plants.
PS maybe Dunstan is only 3/4 American I have top do more research though.
Pure Japanese are tall!
They’re good timber trees, and burnt ridge has a good nut bearing and timber variety, I don’t not know if Chinese pollinate them, but European crosses can.
Well this isn’t the thread for this, but I haven’t heard of Dunstans being 7/8 American. I believe it’s far less. This is the history on them…
Also, I just want the original, native tree back. The tree has gone through a lot of testing in native environments and has shown no negative effects on insects, wildlife or other plants and microorganisms. It’s one gene that lets the tree detoxify the fungal blight with oxalate oxidase which is found in many other plants. I understand the concern…like I said, I’m not a big fan of GMO. But in my opinion, this is a minor change that will result in a great positive impact on the native forest diversity. And yes, the trees can still mutate on their own…not sure where you got that idea?
And there has been a lot of disappointment with some in TACF circles with the 2nd gen hybrids and how they still take on too many Chinese characteristics. Many have jumped ship and put their efforts in Dr. Powell’s work with the Darling trees.
All chestnuts are nice trees. I’m not trying to put down hybrids or trees bred for taste and size. I just want a tree that is functionally 100% American.
But yeah, they’re all easy to care for. 
I just cut down a 75 year old chestnut that produced an insane amount of nuts most years. I always struggled with worms inside the nuts. Worms were in 90+% of the nuts. My tree was probably 70 feet wide and 50’ tall so spraying it was not an option. I still have one tree left.
Wow. Is it possible for a regular Joe to get ahold of these trees? I would love to plant some, even just in the woods. I have a few blight-resistant hybrid cultivars and a Dunstan Revival in the ground already, and a few potted Chinese chestnut seedlings with purportedly good genetics that I was going to plant this season, but if I could get real dentatas… I might amend my plans.
Sorry to ping you @castanea but do you have an opinion about this project?
Federal regulators have not yet approved them. That should happen later this year, but it will take awhile for the average person to be able to get these trees.
Dunstans are more like 5-10% American. Most of them have virtually no American characteristics at all.
The Colossal seedlings will die of blight or root rot.
Replace them with Chinese seedlings.
Outside of Saltville, Virginia was a chestnut tree that I assumed to be a native. Very tall and producing nuts as of (12?) years ago when I last visited it. I had read that there are stands of blight resistant trees throughout the states. Message me directly if you want an accurate location to try to collect nuts.
Here’s the SUNY ESF 2022 progress report.
Maybe a donation to the NY chapter of TACF would get you on the list sooner? Not sure. I’ve had some email convos with Dr. Powell in the past, but not since he posted about some bad health news earlier in the year. So I’m not sure if I’m in line for a couple of seedlings or seeds either. I have a tree about 25-30ft tall just in my back woods and 7 others I’ve planted on my property about 5-6 years ago. One of them flowered for the first time last year so I’d love to get one ASAP.
I have both Chinese and Dunston in central Wisconsin. Their greatest nemesis so far has been Japanese beetles, followed closely by rose chafer beetles. If you get either of those you’ll need a plan to deal with them.