Sorry, but it is toast :-( I don't see any viable buds on the upper portion and it should be fully leafed out by now or close to it. And the black tips are an indication of a bacterial blight that can be very damaging and even fatal to colored bark JMs.

But the rootstock is alive and doing well! Just not going to produce the same tree you purchased.

And fwiw, I doubt that was ever a 'Sango Kaku'. The bark is far too pale and yellow in color, whereas SK's bark is a deep reddish orange. Looks more like 'Japanese Sunrise'.

Sango kaku will never have yellow bark. If dead, the bark will darken to a deep reddish brown or gray. The name itself means 'coral tower'.

btw, JMs are often purchased by mail order from specialty nurseries because a full selection of cultivars is rarely available at most retail nurseries. Even my large local nursery only carries at most about 100 different cultivars, which barely scratches the surface.

Thank you.

It was bought from a well known commercial nursery (probably of the biggest in the bay area) and it was definitely meant to be/labeled Sango kaku. Also, the bark was red when I got it. It turned yellow earlier this year.

If the root stock is alive, should I trim the black branches and wait or is it time to take it out?

I am also curious, what caused this? The sun exposure or something else?

There is nothing alive except the rootstock so your choices are to leave the topgrowth in place as bare, dead stems (not recommended); cut it back to the graft point and let the rootstock grow; or remove the entire thing.

Why it happened? Could be a factor of several things. Sango kaku is one of the more popular JM cultivars and there are many on the market that are of inferior quality because of poor propagation methods, including many that are seed grown (much like Bloodgood frequently is). This could account for the yellow stem color. Errors in planting and aftercare could also account for the rapid defoliation. And finally, most JM's that feature colored bark, like any of the coral bark cultivars or the orange fading to yellow bark coloration of other cultivars, tend to be overly prone to the bacterial blight (pseudomonas) which is both disfiguring and potentially very damaging to the health of the tree.

Hopefully the nursery you purchased it from has some sort of a warranty program that will replace it or credit you for the cost.

I was told this tree will tolerate the sun as it origins from Pacific Northwest.

==>> boy thats a non sequitur ... how is the blinding light of the PNW make a plant thrive in full sun in san fran ..

not to mention latitude increasing the intensity of the sun ... thats almost like saying it grows in full sun in MI .. so it ought to do well in GA ...

this midwest guy is asking ... having no particular experience with the left coat places and climes ...

anyway ... sun reflected off that white wall could have been an added variable .. it got toasted.. and no amount of water to the roots could offset it ...

the tree coming from the roots doesnt look to bad ... but if you have a warranty.. take it back..

ken

A yellowish one that has been on the general market here in later years that I tried was 'Bijou'. It always had blackening from the tips back except for a year I fertilized it. Instead of keeping up this regime I decided I didn't want to bother and removed the tree.

Sango kaku is rated one of the better JMs for full sun. It is also highly rated for heat tolerance. But that has nothing to do with the PNW :-) It was actually developed in Ireland in the 20's.

And Bay area weather is not terrifically dissimilar to that of much of the PNW.....a touch milder in both summer and winter and less rainfall but with few days of intense heat and sun. Doesn't get nearly as hot in the Bay area as it does here in the Puget Sound basin! If it will tolerate full sun here - and it does - it will also tolerate it there.

This is likely nothing to do with either too much sun or heat.