I'm not interested in working on the route, but I am familiar with the area. It's not really desert as you think like that in Arizona. This area is dry, but is tall dry grass, bushes, small cactus - mostly prickly pair type, wildflowers and creosote.
The soil is very light colored as it is high in limestone, however, there are some areas with red sandstone as well. It is also not a flat area. There are some rolling, hills and even some mesas and buttes around. I have an amazing picture of a super cell coming over the top of a butte just east of Tucumcari.
The roads are mostly dirt except for the main roads and a couple of side roads. My suggestion is you take a look at Google Earth or even Microsoft Bing Maps to get a good idea what you are getting into.
I was out that way in May 2013 while severe storm chasing. We drove out of Amarillo, TX and followed the old Rock Island mainline. You can still see some old track while in other places piles of ties and in others just the bridges. It's as though things were left in place and are slowly being ripped apart. I wish this line was still in operation, but sadly parts have become rail trails which means that will never happen.
John