Several species of trees that are native to Colorado may be suitable for your landscaping need. Most of these are drought-resistant and beautiful.
At the top of the list is the Colorado Blue Spruce, the official state tree. Other fine additions to your landscaping plans may be the Lumber Pine, Wasatch Maple, Ponderosa Pine, and Scrub Oak, also known as the Gambel Oak. All of these natives thrive well in the vagaries of the Colorado seasons, unlike some of the transplants you may initially consider. If you are desiring of fall color around your property, the Wasatch Maple is a good choice.