JBP next steps?

[harshadg]

I recently acquired this 2-needle pine (which I believe is a JBP kotobuki - I could be mistaken. The seller had no idea of the species). It was balled and burlapped and basically left to die and so has essentially been neglected for several months now. Once I acquired it I slip potted it - root ball and all - into regular garden soil, since I wanted to avoid doing anymore damage to an already disintegrating root ball.

It seems to be doing fine so far in that the needles are extending. I know I need to do two things: first, deal with the roots. It’s been burlapped for a while so the roots are obviously not spread out. And second, at some point I’d like to get rid of the sacrifice trunk. Of course I’d like to prioritize the health of the tree over any of these decisions.

Ideally when I do the root work, id like to be able to change the angle and select another leader to grow it out more and build taper. What would be the ideal time to reduce the trunk? Am I ahead to wait until spring 2024, repot it and spread out the roots first before dealing with the trunk? Or is it better to chop the trunk sometime this year (fall? Now?) and then repot next year?



Thank you for any suggestions!

Cheers,

 

[BonsaiDTLA]

i still see some buds and needles close to the trunk, but on the lower trunk it's very sparse.
If it's growing well for you, I'd weaken the leader by removing many of those branches up top. Let the strong one keep going but that would divert the energy lower.

 

[Lorax7]

I’d do the root work first. Foliar mass helps drive root growth. If you remove the sacrifice branch first, you decrease the amount of auxin and sugars that are produced in the needles and transported downward, driving root growth.

 

[harshadg]

Thanks, that makes sense.

It seems that I should just grow out the tree this year, make sure it is healthy and then do root work next spring.

 

[harshadg]

Here's an update on this material.

I have two of these pines that I rescued from a garbage heap. I decided to keep the top growth on one and chop it off on the other. Over the winter I only protected them from the harshest temps but they largely stayed out. A distinct possibility here is that I may have failed to identify when they needed to be promptly watered as temperatures got warmer.

In spring, I repotted these into pumice straight, keeping the core of the rootball untouched. The large chunks of clay essentially fell right off so this was easier than expected. In the case of the pine with the top growth untouched - I saw a respectable amount of root growth all things considered. OTOH with the tree with the top lopped off, I found mostly dead and decaying roots and abysmal roots. This may ofcourse have something to do with the fact that I found them in bad condition to start with. If I could do over - I’d have followed the advice given here for both.

This year they’re both in Anderson flats and put out new growth - lagging behind the seedling JBPs by 1-2 weeks.

In the time that I’ve had it, the needle morphology has massively changed. From short kotobuki like needles to wildtype JBP. This has left me with an unknown - is this even a JBP?

To test this, I decandled one of the candles on the healthier tree in the top growth. A single new bud popped up in its place. I was expecting more buds - but any insights would be welcome.

The plan here is to keep them in these flats while they regain health. I will also be keeping them in a garage over winter.

Attaching pics for reference. I think the needle browning is too much sun and not enough water in early spring.