We are on a one acre lot and would like to plant something along one of our fencelines to hide our neighbor's messy yard from view. We have a lot of deer, so as deer resistant as possible. We can get water there but would prefer something native/natural. (If watering it will make it grow faster, then we'll do it.)
There are several shrubs native to Eastern Oregon that could work for you, depending on how large you want them to be. I think you will find this publication, "Selecting native plants for home landscapes in Central Oregon", quite helpful. Match the cultural conditions of your site (full sun or part shade? Dry or moist?) to the plants in the list to narrow down the selections.
Some that you might consider include Mountain Mahogany, (Cercocarpus ledifolium), and Buckbrush (Ceanothus velutinus), which are fairly large evergreen shrubs. I can't guarantee deer resistance, since they will eat anything if they are hungry enough, but the native plants are generally adapted to deer browsing.
It is generally a good idea to water sparingly the first year or two, to help your new plants get established, but they should be drought tolerant after that. While additional water may make them grow faster, it will also make them more attractive to deer (and other pests), so that is a mixed blessing!