shishigashira

I have dozens of JM's, many of mature size, and have found them over the years to be generally trouble free. Among them were 4 shishigashiras planted 10-15 yrs ago. The shishigashiras grew nicely (though slowly of course) to be eventually 5-6ft tall each. Over the past 3 years, I have lost 3 of them and the one remaining just has a single branch leafed out this year, so I presume it's on it's way out also. I rarely have lost any other JM's (I must have 50 others...), so I'm wondering what's up with the shishigashira's? Are they known to be more prone to disease or weaker plants because of their severely distorted leaves? Has anyone else had trouble with shishigashiras?

That is tough to lose all of them - i have not had any issues yet with my shishigashira it has been in the ground 6 or 7 years to this point.

From time to time I will lose a jm although it usually from splitting trucks - and two last year to some insect that refused to die.

have you looked for black discoloration inside the tree trunk?

One of my shishigashiras was planted right by the walk to my front door,
which is a measure of the esteem I have for this cultivar.
The tree had 2 main trunks, one of which abruptly died mid-summer '13.
I cut that trunk off and you could see dark discoloration in the cut trunk.
I foolishly left the remaining healthy-looking half (wishful thinking),
which of course went on to decline & die over the next year.
Refreshing my memory by looking at the pictures,
I can see the tree was taller than I remembered, probably about 9ft tall.
I have two remaining shishigashiras, both about as tall as this one,
but both in pretty miserable shape, just one or two branches leafed out.
I presume I should remove them, but it seems criminal.

#1 is the wilted foliage. Appeared abruptly mid-summer.
#2 shows Rt (smaller half) with healthy foliage, Lt wilted.
#3 is the cut trunk showing dark discoloration.
#4 is the severed half of the tree.
#5 is the remaining portion of the tree showing discoloration of the cut stem and healthy-appearing foliage on the remaining portion of the tree.