That's not the real threat for confiscation of private land.
Imagine that you own 1,000 farm that you inherited from your daddy.
In order for your son to carry on the family tradition he's going to have to pay 55% of the farm's value to Uncle Sam in death taxes.
He won't have it; so he will lose the farm.
Confiscation of large privately owned farms in the first thing Communists do when they take control of a nation.
It's also why Communists start going hungry soon afterwards.