Poplar uprooting?

[stang1911]

Hello, long time lurker first time poster.
I have a poplar that is slowly bringing it roots above ground. I didn't think much of it til I was pruning it the other day and found what looks like a lightning strike at the top. I took off about 5 feet and the pith and half the heartwood is black.
My question is, is my tree dead? I can get pics tomorrow of roots.