Second picture

winter damage for sure..

anything not leafed is dead.. prune back to a live part ...

i suspect .. and i cant tell from these pix ... that the harm.. went down inot the main trunk .. and it is struggling to push leaves in the part damaged part [???] ...

i would look to the trunk.. just below.. where the red leaves start ... and see if you can see anything ... if you do.. i would probably cut off all above.. and let it focus its energy on the good parts... rather than wasting it on trying to rescue a damaged part ...

in other words.. there seems to be a pattern to the red leaves... if you stare at your first pic ... trace such down the trunk ... and see what you find

lawn looks weed free ... is it sprayed... can we deduce anything from that???

ken

That does not look like winter damage to me. How much rain have you received this season?

It also seems rather exposed. Amber Ghost is considered a reticulated form (light foliage, darker veins) and can certainly be adversely affected by excess sunlight. Even in my very northerly and mild summer location, any of the reticulatums including the Ghost series would be best sited in afternoon shade at the very least.

I'd also be shocked if that was winter damage in zone 6B/7A. The stems certainly don't show it.

I had some dieback on mine and based on what some claim I would have had a zone 3 winter.

I'd ask the same question as to how much rain you've had recently and what type of soil you have. JMs tend to demand well drained soil.

I doubt drainage is an issue as it seems to be the top of a hill, and the OP suggests it's been there multiple years. Also from the look of the grass, there has been enough rain. Lastly it appears that mainly certain branches are affect. IMHO it probable has Verticillium (or similar vascular disease) from the limited info we have. My second most likely cause would be root issues due to root stock being kept in one of those tiny seedling pots too long.

Arktrees

I have a purple ghost which gets a bit stressed in mostly sun over the summer. Now it looks pretty good. A month from now....

FWIW the Purple ghost was half covered in snow for a month and did not loose a bud. My Higayasayama (spelling) lost a dozen 4" branch tips and looks ragged this spring compared to most.

The issue is perhaps too much water, not a lack of it. I am not sure the planting site is on enough of a hill to guarantee good drainage and the planting area looks to be well amended also.

Also, these types of JM's can experience bacterial canker that result from winter cold damage coupled with moist springs. Since a major portion of the country has experienced a very bitter winter and an extremely wet spring, disease issues at this time do not surprise me.

I'd be very reluctant to diagnose Verticillium wilt at this point. The symptoms do not match very well and the timing seems to be off a bit as well. VW with JM's is typically visible right after leaf out or by periodic branch die back (which can happen very rapidly) later in the season.