Also you'd be in desert like conditions all the way pretty much.
Hmm.. Dunno.
Sure, a big chunk would ber desert, because it was desert before the great war.
like, pretty much from Cali toabout half way through Texas or say the Kansas/Missouri border, youre looking at pretty close to desert conditions, unless youre passing the souther rockies, or cossing further north through the Dakotas. Thats the way it was when settlers traveled west. They cut across the north and down to Cali to avoid some of the desert and still made it from STL to cali in about 6 months.
We know that since CL has picked up so many tribes along its path that there are places we can trade through some of that.
We know the courrier has been as far as the continental divide, which I usually place around the arizona NM border.
More than just stating that a person cal walk it. It means that there may be knowedge of the paths to take.
Unless we head further north to the great lakes area, its really between the missisippi and the east coast that we dont know about for sure.
But that is only about a 5th to a quarter of the journey, where i would argue there would be the best chanses for agriculture and fresh water from spreings and aquifers..