A. Insurance covers:
(1) Property: home owner insurance covers your house, auto insurance covers your car
(2) liability: the fault you did to other people. auto insurance covers your fault when you are driving, and home owner insurance covers the fault you committed when you are not driving (negligence, defamation etc).
B. Your problem is,
The property portion of your home owner insurance only covers the house.
The property portion of your auto insurance? It's called comprehensive coverage, you didn't buy that portion. You bought only liability.
And the tree falling on your car is an act of god, it is not covered by any liability portion of your insurance.
You are out of luck.
C. However, your loss is probably tax deductible.
https://www.irs.gov/newsroom/top-10-tips-for-deducting-losses-from-a-disaster
See "Casulty loss"