Starting a new game with the USA DLC and I really have to laugh about this.
It may be news to some of my European friends, but not all of the United States is covered in desert, in fact we have some vary lush green covered landscapes, well at least for another fifty years 😉
If you select ‘custom’ when starting a new game you can select the European green texture and combine it with all the other US features. This will give you the green US landscape that you desire.
You can also have a European desert landscape as found in southern Europe.