When I toured the Jack Daniels Distillery 20+ years ago they talked about the wood they charred and used for filtering and how they didn't know how why this made a better whiskey. My friend and I, both chemists, laughed and offered to explain it to him.
It's a common misconception that vodka is made from potatoes. Most vodka is made from grains. I learned this touring the vodka museum just outside Moscow a few years ago but I'm sure google can verify.
Ultimately if one just wants ethanol and water whether for whiskey, moonshine, vodka, etc. just about any plant that can be fermented will do.