I did a GOOGLE search yesterday, on one of the names on the pictured headstones.? It came back on Rootsweb.?
http://ftp.rootsweb.com/pub/usgenweb/or/umatilla/cemeteries/foster.txt
It seems that in 1937 some work was done there by the WPA to catalog the graves.? The report there also mentions a property owner for the cemetary. That might be a starting point to trace who is the owner of the property today. There is a listing of the readable graves that were there at the time.? There is a listing from the records of that cataloging.
Later, in 1963, another survey was done and some of the previously cataloged graves could not be found. Again there is another list of what should be there.? ? Some stones were mentioned as broken and others, that were made of wood, were no longer there.? It was mentioned and dated around 1965, that there were a couple of coffin sized holes observed.? Also, it is believed that the actual cemetary might extend beyond the boundries of the existing site.? ?
I am assuming that the Rootsweb listing is the same as the cemetary that is mentioned here.? The Cemetary name is the same., stone inscription seems the same.? Both are listed as Oregon.? I looked up Andrew P. Tribble.?