I would vote to give it the "one cut prune" at the ground. It looks to be unrecoverable.

we would have to start by IDing it... which i cant do.. because it is dead ...

i highly doubt.. with those giant wounds... that is was a bug issue ...

do you have any old pix of it to ID it ...

are any of the shoots near the bottom... suckers.... or all other stuff ..

if suckers.. you may still get the plant back.. in a new shape and form ....

if not.. its dead.. above and below ground ...

ken

See the left half of the picture, the green behind the dead trunks are the living trunks (%30+) of the tree.

I wonder if this is caused by some insects and some chemical may help?

Can you take a small piece of foliage, lay it on pavement, and do a close up photo of it? Then it can be identified and better recommendations can be offered.

See the left half of the picture, the green behind the dead trunks are the living trunks (%30+) of the tree.

I wonder if this is caused by some insects and some chemical may help?

Can't tell without a better picture.

But the dead parts are dead. Cut them out.