That wasn't tree falling in Ohio, that was overloaded line sagged and shorted into a tree, compounded with several other factors that contributed to the grid instability and the inability of the grid operator to realize how unstable the grid was.
I think the point is that neither of those events should take out a whole city; the design is such that there is considerable redundancy in the system.
Relying on vegetation management along millions(?) of miles of lines is the definition of thinking you're in control without even knowing what risks exist. I see this every year in Texas, they trim back trees thinking they have solved the problem - except - they are allowed to trim them back I think 6-8 feet from the lines, ignoring the fact the trees are 20-40 feet taller than the lines. Nobody seems to see the risk that they left there but it's quite obvious to me, we're not eliminating risks at all. We're minimizing them at best, and even then the labor required to trim all the branches around lines every year is impossible to keep up with from an economic feasibility standpoint.
