What types of grasses and plants sustain harsh winters, hilly, sandy soil, and road salt?

Buffalo grass (side oats gramma) is very hardy and can take just about anything.

This site lists the plants and grasses native to Northern Michigan (thus likely to be able to withstand the conditions).

I learnt at college that you need a mixture of diffrent types of grass seeds when growing a lawn as one type relys on another type to last that’s why when you buy a box of grass seeds there usaly a mixture of types in it.