It turns out that the energy of the impacting object is the measure of how much it destroy… but of course the crumple up steel boxes damage themselves so thats an adjustment to make… but the damage done to the vehicle must have taken a heap of force from the tree, right.
But from experience ( regional area… our slipperly roads surrounded by forest), 40 foot pine… its about a foot diameter at the base… bit much for a car to break especially as its a living tree not a wooden pole harvested 20 years ago. Green wood is tougher… takes more energy to break.
Cars will explode apart rather than knock the tree down. Cars might snap the older pole if its around a foot diameter and its nearly too old… much more brittle.
The tree may now be mortally wounded though, it needs its bark and roots undamaged.
The pickup truck , 60’s design more so, less so as the decades go, might break the tree rather than the vehicle exploding around it, and bigger trucks obviously take a foot diametre trunk out. If they hit a 6 foot diameter tree, the truck may be exploded instead , until the damage area diverts the rest of the truck… (some cars have been split in half down the middle, but trucks don’t. theres various shapes inside the truck frame which will tend to steer the rest of the vehicle into a rotation… so it then goes around the tree in a spin …either the tree breaks or the truck spins.)