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...