JBP in possible decline - Pleas HELP!!!

[dansai]

I repotted some Japaneses Black Pines in late August. They had been dug from a field 3 years ago and had a lot of fine clay/silt still at the base and had been placed in a quality bark based potting mix (not by me). I removed a fair bit of the field soil, leaving only a little at the base and keeping as much live roots as I could. There wasn't much. All were potted into 1:1:1 Hard Akadama:Pumice:Scoria

One has killed off a couple of branches and although it's candles have started to extend, they seemed to have stalled a little and the needles around are losing colour.

Sick JBP - 3.jpeg

Another one the candles had started swelling but there is no sign of needles and it too has started losing colour in the last week or so.

Candles

Sick JBP - 1.jpeg

Tree

Sick JBP - 4.jpeg

Another at the same time is going well. You can see it in the above picture to the right. And below a close up of the candles.

Sick JBP - 2.jpeg

I also potted 2 other trees around the same time that were from a different lot and didn't have the field soil. Both are powering away.

So, is there any expert opinions on what I can do? Is it just a slow road to inevitable death? Can I save them? Or at least do something to give them the best chance?

[Ryceman3]

I’m not sure “expert” applies but if the condition of the needles is the same across the entire tree I am first thinking you have a root issue, and from the colour and condition of needles I am leaning towards something fungal. Phytopthera spp is a first guess… I would think about a systemic that can be applied as a soil drench, but maybe also do a spray of the foliage and be diligent with watering (as I’m sure you are).
I think you have secondary issues that might possibly be capitalising on the weak health of the tree too. The base of the bud in your first pic looks very dark (sooty mould?) that might be a result of the white fluffy dude next to it… probably either woolly aphid or pine adelgid. I don’t think this is the source of your issue though.
All the best with it, not sure that helps much!

[treeman]

I removed a fair bit of the field soil, leaving only a little at the base

The base is the worst place to leave it. It can be the seat of many troubles down the line.
The way to save it is take it out, remove any old field soil, wrap the roots in moist (not wet) sphagnum then cram the whole thing into a terra cotta pot which barely holds the root ball. If there are any gaps fill them with clean sand or pumice. Not a guarantee but I saved a cedar and a pine or two by doing this. Mist often and only re-wet when it's almost dry. The terra cotta pot (preferably a new one) is vital. You must be extremely patient. It will take a year to recover. (if it doesn't die first)

[dansai]

Thanks for the replies.

I believe it is a root issue. Like I said there weren't many roots to begin with. Crappy field soil left on the tree and far too much of it. I did clean out directly under the base as much as I could and only left areas that had roots in them. The plan was to revisit in it a couple of years to remove the rest. My concern is that the tree won't be around in a couple of years and wondering if there was anything I could do in the meantime to assist in its ability to survive.

One thing I have considered is doing another repot into pure pumice. I know that it can be good for freshly collected conifers, was wondering if it may be able to help here.

The colour change has only happened in. the last 2 weeks. Nearly 2 full months after the repot. I understand some of the growth may have been from stored energy so I'm concerned I'm not getting new root growth.

And yes Ryan, I did have some pine Adelgid which ive sprayed for twice.