Tight Wad
 

Holy cow the tree is on your property-take it down. I would be very disappointed to have a neighbor that doesn’t take matter seriously and remove the tree because of cost.

My thoughts also.

How would a fallen tree sink to the bottom of the lake as a fish crip,
wouldn't a dead tree float?

have it taken down on the ice in the winter and it can be easily cut up and stacked on the shore for removal in the spring

Was in the insurance adjusting business and agree with most of your thoughts. Many people use the term "act of god". Will not find that term in the law. Over the years people have used it to refer to weather events.

In our litigious society if the tree hit a person and killed/badly injured that person you can or should expect that the person will try to find blame on the tree owner. There are a lot of "paid experts" out there who will make an arguement that the tree was likely to fall or the owner of tree knew or should have known that it could fall. If something did happen, if you have a Homeowners policy with liability insurance. they would respond to any claim and/or lawsuit.

Was in the adjusting business. Most policies are called all risk policies. In other words the policy pays for all types of damages caused, EXCEPT for certain causes(such as war, wearing out, flood) In Florida, your insurance company could try to recover the money paid out if they could show that the neighbor had a bad tree and knew they had a bad tree

Great response.

If you know, or should reasonable know that a tree is dead or dying (both of which you have admitted too), you would be found liable if the neighbor can prove it. If a healthy tree falls due to wind, it would be considered an act of nature and you wouldn’t be responsible.

Tree falling.
 

A tree fell during a stormin Indiana. It caused $7,000 damages. Our insurance had to pay, not the neighbor whose tree it was. I don't know FL law.

I could be wrong, I’m not an attorney, but if your neighbors dock is in the lake and your tree falls on it, I doubt there would be any recourse to you since the dock was not on your neighbors property. Your neighbors land does not extend beyond the high water mark of the lake. In addition, if the tree is noticeably at risk of falling in the direction of the dock, it should be a reasonable expectation that your neighbor should assume responsibility for putting their dock in harms way. All that being said, talk with the neighbor and try to find a mutually agreeable solution to the problem. It’s always best to prevent a problem rather than wind up lining the pockets of a couple attorneys after the fact.

I'm from Virginia. There, if you didn't know the tree was an issue and it fell, the neighbor's insurance would be responsible. If you knew it was a problem and it fell, you would morally be responsible. If your neighbor and you both knew there was a problem and you didn't do something about it, you would be responsible.