Stunted Chinese Chestnut Trees

Hello all! I grew out a few chinese chestnuts in air pruning beds and then transplanted them into my fields in 2023. At the time of transplanting they were around 18" tall. Now after two years in the fields they are only around 3' tall, but they have put on lateral growth. I understand that taprooted trees don't love being transplanted, but I figured the air pruning bed would help with that. I've heard that chinese chestnuts can grow 1-2' a year when young, so their short stature is a little concerning. My soils are well-drained loam, with a decent amount of iron in it. The trees received a small helping of compost in the spring and then primarily rainwater. We have been experiencing a severe drought here in Southern Maine, Zone 5A, which definitely isn't helping.

Any insight would be much appreciated!

I wonder if something came along at some point and nipped off the leader growing tip, if in fact the trees ever had any?  In any case I wouldn't worry too much about the shape, you will end up with nice spreading trees with strong crotches the way they are.  You might pep them up with good mulch around them, out to the drip line for a couple more years to reduce competition from the grass etc.  And remember, "water is the best fertilizer".  If your veggies are going droopy from drought, trees this age and younger will benefit from watering too, even if they aren't showing signs of stress.

Is you soil rocky? That can sometimes result in stunted plants, at least where I live.

You might try some compost tea or weed tea if you don't have compost.

The soil is definitely rocky. Plenty of fist sized rocks and the occasional small boulder. I gave them one application of compost tea this summer, but it was probably too little too late with the drought.

I don't think anything nipped off the leader at any point, but I'm glad you think the spreading shape is a bonus! I just hope they grow taller than the surrounding goldenrod at some point.

I think your tree looks excellent, except maybe the lack of a central leader. But my impression is that Chinese chestnuts are big sprawling trees (as opposed to tall, straight American chestnut). In Peter Wohlleben’s Hidden Life of Trees he writes that slower growth when they’re young also leads to longer lived trees, because their wood gets to be stronger (closer rings).

Green veins within yellow leaves is typically a sign of metal deficiencies, most commonly zinc.  For my own chestnut trees with the same symptoms, I made a spray bottle full of 1% zinc sulfate + a drop of detergent to spray on the leaves.  After spraying, the leaves started greening immediately, within 1-2 days.  Amusingly, the greening followed the spray pattern exactly.

If you can't find zinc sulfate, the commercial fertilizer "Ironite" will be a source of zinc.

Supposedly, what some old-timers did for mature trees was to drive a few galvanized nails into the roots of their trees?

I don't have a lot of experience with Chestnuts, but what you show is what I've come to expect in my conditions.
I have only one Chinese Chestnut in my first plot; the majority of what I have are crosses of European, Japanese, and Korean types.
I didn't start from seed; the trees I ordered were probably 3-years old when I planted them (twelve years ago maybe?).
I watered them the first couple of Summers to get them established, then let them go.

It took a long time (six+ years?) for them to get some real height - though they are unirrigated and often-pruned by Horses & Deer.
They seemed to appreciate volunteer chaperone Blackberry brambles joining them that keep the browsers at bay.
Now they tower over the brambles and have started making some nuts the last couple years (eventually I'll cut out the brambles).
My Chinese Chestnut hasn't made nuts yet though.

I'd say give it some time.  However, more knowledgeable growers may have specific advice that could boost growth rate.
Good luck on your endeavors.

Those look exactly like ours, here in mid Maine. Same age. We had a deer breakin their first year and all the leaders got nibbled. But it’s drought that’s causing the issues as far as I can tell. The zinc idea is brilliant! But water and thick thick mulch has kept them going. The ones I compost tea with comfrey are doing best.

Lotsa' good advice here, I especially liked the suggestions about mulching, compost tea and zinc. I would definitely mulch your trees with compost, wood chips and broom, if you have it.

I have a couple Chinese chestnuts. They were planted as seedlings about 12 years ago. They grew incredibly slow the first few years and I watered them sparingly. I gave them chicken wire cages to keep the deer out.

Several years after planting them, I read that permaculture farmer Sepp Holzer recommended using Scotch broom as a mulch for chestnuts, so I pulled out all my weedy broom plants in that area and heavily mulched the chestnuts with them. I also gave them some mineral supplements the past few years- rock phosphate and an organic sulfur/magnesium/potassium mix. This seemed to make them grow faster and now they're roughly 18 feet tall. This year they finally flowered for the first time, but the nuts did not fill out.

Anyone here have luck with Chinese chestnuts in the Pacific Northwest? Do they require irrigation to form nuts in our dry summers? How about zinc supplements to help the chestnuts form? I've read that local filbert farmers use zinc supplements.

M.K. Dorje Sr. wrote:Anyone here have luck with Chinese chestnuts in the Pacific Northwest?

Pacific "Southwest" here, but my observation may be helpful. I have noticed that chestnuts do not want to get established in my area - I have tried 10 different hybrids/species. Chinese chestnut looked promising but was  destroyed by 2024 summer heat. The other ones usually were done by June. They were also sensitive to late frost that defoliated them and then they did not have enough energy to develop more leaves in the heat.
I was purchasing seedlings and quite large grafted/layered trees. They would need shading, more watering than my regular irrigation schedule and they prefer acidic soil, so not very permie in my case. From all chestnuts that I had only one survived: Layeroka (from Morse Nursery) - hybrid of European and Chinese chestnut. It's been over 2 years in the ground and is growing slowly, under 1 m tall, but with lots of branches.
If I ever tried another one, it would have to be in a different location on my property in half shade, flat terrain, lowest spot (more moisture).
After checking where chestnut plantations are successful - I'm not shocked that they would not stand aridity - especially Chinese one that originates from the wet and not too sunny eastern China.

Thank you Cristobal! That is the  kind of info that I was seeking, although I'm bummed to hear that you've had little success so far. It sounds like I might need to irrigate my trees more to match the environment and climate that they are from. But I love chestnuts and I'm  determined to get some nice big fat ones next year.

All this talk of Chestnuts got me curious, so I went out to check mine.
I found several pounds of big, beautiful marrons on the ground from two trees!

Not trying to hijack this thread from the OP's question... but regarding whether they will form nuts without irrigation - YES!

I'm about an hour inland from the coast (PNW).  The only watering they got was the few times it rained this Summer...
This is very encouraging to me, as it is the first year I have gotten more than a handful... so PNW Chestnuts w/out irrigation YAY!  
One of the trees is probably fifteen years old, the other is only seven years old maybe.
Neither is a Chinese Chestnut, though...

I've got several seedlings started this season collected from mature healthy looking asian (hybrid?) stock in an old neglected orchard nearby, probably 50+ years old along the upper margin of unirrigated pasture on a bench above Klamath river near Oregon/Cal border (average maybe 20" annual precipitation). I'm planting directly in probably neutral or alkaline native grassland soils, plus some biochar and mulch. Many are situated in part shade + browse protection under nitrogen fixing shrubs (ceanothus). Will be doing a little supplemental watering over summers 1 + 2 at least, and occasional nutrient tea. Honestly don't expect great success, but a handful of survivors would be worth it! Good pointers noted above; I'd be curious to hear any more reports from dry/mediterranean zones. Would (southern) European species or crosses likely perform better?

Ben,

My Layeroka has more spreading branches and some flowers now so I'm excited about a possibility of first crop. With my three new beehives there is a chance.
I have also got in January a massive seedling of Colossal. It was so thick - around 25 mm/1" trunk, that I could not resist to not purchase for only $30. Maybe it's not the best cultivar, but all the best that I had have died, so I will be happy with any living chestnut. Just in case in summer, I'm going to shade it with some cloth.

Your location should be more agreeable with chestnuts. When I travell I see chestnut orchards north of Sacramento, but never at my lattitude. It's just more moist there. and the sun is getting less intense. If you planted in half shade they should be fine. I'm using some sulphur pellets mixed into compost to increase soil acidity.

The zinc spray tip is really interesting, I wouldn't have thought of that. Rocky soil with drought on top of it is a rough combo for anything establishing. Sounds like the ones getting comfrey tea and thick mulch are pulling ahead though, which makes sense. Chestnuts seem to just want to be left alone with decent moisture and they'll sort themselves out eventually.

There's discussion in David Jacke and Eric Tonesmeier's 'Edible Forest Gardens' about grassy areas having bacteria-dominated soils, while forests have fungi-dominates soils, and that trees struggle to establish in bacteria-dominated soils.

I've spread spent mushroom compost from a local grower across a lot of my garden over the past year & have had a lot of mushrooms growing this autumn (sorry, "fall"...southern hemisphere!), so if you can get it perhaps adding some of that with woodchip mulch would be a useful addition...

Perhaps Zinc sulfate, humid summers work well with zinc spraying leaves, yet I like root absorption.  Zinc does not fall from the sky, without a large volcano upwind, and you don’t want that.  A ring  ZnSO4 about 3 feet out a little goes a long way, and don’t fertilize as that will make it worse.  Cheers.

M.K. Dorje Sr. wrote:.

Several years after planting them, I read that permaculture farmer Sepp Holzer recommended using Scotch broom as a mulch for chestnuts, so I pulled out all my weedy broom plants in that area and heavily mulched the chestnuts with them. I also gave them some mineral supplements the past few years- rock phosphate and an organic sulfur/magnesium/potassium mix. This seemed to make them grow faster and now they're roughly 18 feet tall. This year they finally flowered for the first time, but the nuts did not fill out.

Anyone here have luck with Chinese chestnuts in the Pacific Northwest? Do they require irrigation to form nuts in our dry summers? How about zinc supplements to help the chestnuts form? I've read that local filbert farmers use zinc supplements.

Great advice to pass along about scotch broom mulch! It has been shown to improve native pnw and norcal tree regrowth where it is mowed and mulched with or left to grow vs herbicide or pulling and removing. I hadn’t thought to use it on the hundred or so chestnuts I planted out this year, but I am going to brushcutter mow mine broom where it will mitigate fire risk to big trees and structures.

I agree it looks like a micronutrient deficiency (ie zinc) from the yellowing older leaves. I would foliar feed with a compost extract-kelp-glacial rock dust spray the entire plant, especially undersides of leaves where stomata are. Plants foliar uptake is a remnant of their marine ancestors, a bit how our lungs can only absorb fully hydrated oxygen due to our submarine gilled ancestry. Jon Kempf has cited 4-70x the uptake efficiency of foliar feeding vs soil application, depending on the mineral and plant species. I would still also soil drench with the same solution as above at least once in the spring.

Max Jenkinstein wrote:... Now after two years in the fields they are only around 3' tall, but they have put on lateral growth... I've heard that chinese chestnuts can grow 1-2' a year when young, so their short stature is a little concerning...
Any insight would be much appreciated!

Hi Max,
A couple of years ago, we visited a chestnut forrest area in France. (They were probably not chinese chestnuts). The younger trees looked a lot like yours. The soil had a lot of clay. When I look at your tree, I see nothing to worry about.
Some groundcover was growing in the wood, but it was not grass. I remember the forrest being pretty damp, but maybe we just had bad weather.

The most interesting thing I observed was the coppicing. Most trees were regrowing from large stumps. We asked locals about it. They grow the chestnuts for wood as well as nuts. We were shown a beautiful, brand new building made from large chestnut wood beams in a warm golden redish colour. After harvesting wood, the stumps would regrow. By managing the regrowing stems by pruning thempartially away, or using a chainsaw at a later stage. One could concentrate new growth in a selected number of stems to create straight trunks. Big roots of big trees would regrow fast. I forgot the frequency of harvesting wood, but I remember it being an impressively short time.

So, if you are really unhappy with the shape of your chestnut tree, you can cut it to the ground (if you have the guts) and select for one single straight shoot to regrow. I bet it puts on a few feet of regroth in one year if you cut it in spring and start pruning to one single stem right away. But please try this at only one chestnut first, to see how it goes.... And let us know of course.

Given that this thread was started in late October, I wouldn't worry too much about the yellowing leaves, just looks like autumn to me!

Interesting that the comments say that chestnust prefer acidic soil, as I thought that was one reason my trees (European chestnut) haven't been doing so well. My soil is rather shallow, but generally moist, so I don't think drought is my problem either. I came to the conclusion that chestnuts just don't like Skye.

Nancy Reading wrote:Given that this thread was started in late October, I wouldn't worry too much about the yellowing leaves, just looks like autumn to me!

Interesting that the comments say that chestnust prefer acidic soil, as I thought that was one reason my trees (European chestnut) haven't been doing so well. My soil is rather shallow, but generally moist, so I don't think drought is my problem either. I came to the conclusion that chestnuts just don't like Skye.

Hi Nancy,

1. I noticed yellowing leaves on potted chestnuts I'd just bought, mentioned this to a chestnut luminary, and was told "'end-of-season' disease, don't worry". I was seeing chestnuts in full, green leaf nearby, but I accepted this and didn't worry until the next spring, when, after foolishly repotting using alkaline coir instead of acidic spagnum moss, the chestnuts leafed out their second spring with yellow leaves again. Then I worried again, and contacted an extension agent. Agent Sam suggested foliar-feeding with trace minerals, especially iron. That greened them up within weeks.

2. Could your chestnut trees there on Skye perhaps be suffering amidst a bacteria-dominated grassy soil, where a fungi-dominated soil might nourish them? An acquaintance suggested simply piling woodchips around young trees would convert grassy soils to fungal dominance. (But you might avoid piling chips against the young trunk in winter, to leave any trunk-nibbling voles exposed to predation).

Brian
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Brian Cady wrote:Could your chestnut trees there on Skye perhaps be suffering amidst a bacteria-dominated grassy soil, where a fungi-dominated soil might nourish them? An acquaintance suggested simply piling woodchips around young trees would convert grassy soils to fungal dominance. (But you might avoid piling chips against the young trunk in winter, to leave any trunk-nibbling voles exposed to predation).

Brian, The fact I planted the young chestnuts directly into meadow turf may indeed have been a factor. I have noticed that some of the trees are doing much better than others - maybe genetic variation, proximity to alders, or better soil microlocation (although they were all planted pretty close together in a grove). They seem to be doing better with a bit of shelter, and I think they maybe don't like the salt laden winds here either.
It would be nice to have chestnuts as part of my productive food forest, but I have korean pine and monkey puzzle which are both doing well, as are my hazel trees. It might be interesting to plant some more with some selected microrhyza added to the hole and some branchwood additions to the surface as you suggest.

Nancy Reading wrote:... I have korean pine and monkey puzzle which are both doing well, as are my hazel trees.

That's exciting, Nancy,

Korean pine seems to suffer here in NorthEast North America, from what I've heard.
I've wondered if it might be grafted onto the NENA native White Pine, which I think is related.

Will you taste and evaluate your individual cultivars of monkey puzzle, Korean pine and hazel?

Brian
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Nancy Reading wrote:I came to the conclusion that chestnuts just don't like Skye.

It's quite possible. Native range of European chestnut is located in warmer part of Europe and more sunny than Scotland. American chestnut locations are also sunnier. Chinese chestnut also likes sun and warmth.
I still think that you will find your perfect cultivar/hybrid, same like I did  and I have the opposite problem - too much heat and sun.

Brian Cady wrote:Korean pine seems to suffer here in NorthEast North America, from what I've heard.

Maybe too warm/dry for it? It likes it here so it likes the wet and cool. there's a thread on growing it here

Will you taste and evaluate your individual cultivars of monkey puzzle, Korean pine and hazel?

I certainly hope to! Some of the hazel are already producing nuts (although the birds and mice get most of them!). The Korean pines are about 6 years old, I expect it to be another 5 years perhaps before they start flowering, I'm not really sure. My oldest monkey puzzles are maybe 16 years old, so probably need at least another 15 years....The monkey puzzles are sexed, so I may harvest some of the males for timber - they have lovely straight trunks (even here on Skye). The hazels are mainly for firewood, the nuts will just be a bonus crop, although have potential to be useful in a 'mast' year.

I bought 2 starter Chinese chestnut seedlings 6 years ago and one has died. The other one has been growing slowly, forming multi branches as well. I suspect that it has to do with the location. That site used to be within the drip line of a big oak that was removed in 2019. The soil is very acidic and after years of letting the area grow wild, diversity is still very limited. Two pawpaws planted in the vicinity are only pencil sized while another tree of the same age planted near the garden is over 10 ft tall and bearing.

In the pictures I can see the background is a mixed deciduous forest but in the open area around the Chinese chestnuts are mostly goldenrods and conifer saplings. Conifers can tolerate more acidic and poor soil so it seems the spot is on the way of succession into a pine forest. Putting wood chips around the trees, especially ramial chips will give the chestnuts a boost.

Goldenrod, - Isn't that allelopathic? Maybe chestnuts suffer by goldenrod.

Brian
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