Turnbull NWR is named for Cyrus Turnbull who squatted on what is now the Refuge for six years before giving up........ as many of the original settlers did. Turnbull then was a marshy, swampy area, great for growing grass........... about 1900 there were 200 dairies in the area and WWP built a special electric railway to haul the milk to Spokane for processing. Despite the settlers valiant efforts to dig drainage ditches (6-feet deep and wide through basalt!!) the area was just not suitable for wheat or corn farming. So many of the settlers went elsewhere.
Now the homestead sites might be spotted by looking for old lilac bushes and apple trees. Only a few scattered rock foundations remain.
There were several dozen families that attempted to settle the Turnbull area and descendants are now scattered far and wide. If you have local ancestry, perhaps your ancestor was an original Turnbull homesteader???