Closer picture of the other set near the swimming pool.

So, I cut down the tree and started turning the soil. Yikes!!! There were cockroaches, little silver armored critters (they ball or roll up to protect themselves. Their outer shell reminds me of a armadillo shell.) And other ground crawlers. It looked like a whole nest of them. Something like out of a movie. They were everywhere! So, I put down the Crawling Insect Killer with Diatomaceous Earth. I put down on top of it Palm fertilizer. Hope this does the trick.

A lack of water might be doing it. How dry is it 6 inches down?

Actually with cockroaches and the water bugs (the little armadillo-like guys), sounds like too much water with rot going on. Do you have an irrigation system? Is it leaking?

The leaking of the irrigation system might sound correct. The tree I cut down sprouted out on it's own without a water irrigation and it's roots are tangled around the main irrigation system. I will have to do some more digging around the roots of what is left of the tree.

I will also take a look at the soil 6 inches down. when I was digging up the soil around the tree the soil was moist but not muddy wet. If it's rot I might not be able to safe the palms? :(