This is a 15 years old JBP grown out of North Georgia and I dug it out March of 2021. Since it was grown in heavy red clay, I washed off all the native soil and potted in the 1:1:1 mix in a bonsai pot. Because the pot was relatively shallow, I built a wood frame to raise the soil line so all the roots can be covered. It grew pretty well in 2021. But the top got really dense because the nursery owner cuts the top off every year to keep it short which led to really dense and heavy top growth. During the fall of 2021, I noticed some branches started to yellow and die off. Not too many, but 5%-10% if I have to guess.
Then I moved to Orlando on the New Year’s Day of 2022 due to work. Now the pine has just a few small branches that are yellow and I have not cut them off. Is this normal for a filed grown pine? Or is it a sign of something wrong with the roots that I need to address?
Also, it will start to warm up in Orlando next week and the lowest temp is going to be around 50F in the night. Is the growing season about to start for most trees?
I believe your problem might lie with “washing off all the native soil”
Do some reading on the symbiotic relationship that coniferous trees and the beneficial fungi in the soil have with each other. 
Not sure if it’s a “problem” yet since it grew great last year. If it grows strongly again this year, then it’s most likely an energy distribution issue.
The tree looks healthy.
Regardless, due to the root washing…, I would procure a box of Dr, Earth and sprinkle about 2 tablespoons on the surface. Benificial symbiotic microbiota… and minor fertilizer.
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The tree is shedding under achieving lower limbs, due to the apical oxins produced by ALL of the top growth dominance …
Maybe, leave dead stub for a future jin…
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If it was mine…Draw a initial design on paper-- bottom to top. Pick an apex… or two. Clean out and cut / thin out the top bushy excess… maybe by 1/3. The lower limbs will get more sun…
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You should know the drill. Lots of information in the library!
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Bonsai On!
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Thanks! That’s what I suspected too. Spent 2 hours to clean one side of the tree and cut off a ton of dead little twigs and removed a lot of dead needles that got stuck in those twigs. Now the tree looks much cleaner. No wonder some of the small brands died off. The dead ones were so compact that they don’t even fall off without tweezers. I will turn the tree around next week and clean the other half.
Also found a few borers buried in there. Smashing them felt extremely satisfying!
I learned a long time ago not to bare root JBP’s and, for that matter, other pines. The mycorrhizal fungi in the original soil is important (some would say essential!) for the health of conifers. Bare rooting strips them from the root mass. The way to replace old JBP soil is about 1/3 at a time. Finding a mycorrhizal inoculant online and mixing it back into the soil will help restore any lost vigor.
As per lectures I have had from Ryan’s classes. there is an energy storage in the roots that is spent in the spring candle push. Since this tree is recovering from the root work ( might I add, as others have, Ryan’s words. “Leave part of the roots untouched, especially in coniferous trees”) This is to retain the microbial environment to support the tree in regenerating root mass. So… the first year a tree is repotted, there is the energy spent in pushing out the foliage which was in reserve from the tree prior to collection. During the year of a repot, the tree is working on reestablishing roots, which in pines is where the strength lies. It needs at least a season to recover from a proper repotting then it will recover some of that energy in the fall possibly. Cleaning out dead needles and branches is fine but refrain from reducing any foliage mass for at least a year, since it has depleted its energy and the roots are now compromised , Please wait till it puts on a robust amount of foliage after its recuperating period. This is why It did well at first and had a difficult time later. Dr Earth Life is a good recommendation as some moderate organic fertalizer for the spring and fall. It probably needs a couple years to recover but it will turn out to be a nice tree if it re-establishes its root base.
L’anno del rinvaso è molto importante poiché la pianta deve recuperare le energie per lo stress subìto e quindi è meglio non fare lavori importanti ma lasciare crescere la pianta liberamente. Ti ricordo che le micorrize sono estremamente importanti per le radici delle conifere,quindi fai un inoculo di questi funghi benefici e vedrai come la pianta riprende vigore.
It’s doing great! I actually moved back to GA this spring and the tree really enjoyed the hot summer and this cool fall. The needle extension is over 6" long because I didn’t touch the tree for the past 2 years besides removing dead branches. I think this coming winter I am going to set the structure and really put some heavy wires on it to lay the branches out. Very excited to have about it!