Yay! I love it when a hunch pays off! The Anna J. Turner buried in Marion County is your Anna.
I found these two death registrations:
Anna J. Turner
Date of birth April 2, 1851
Date of Death June 2, 1938 Methodist Old Peoples Home, 1625 Center St. Salem, Oregon
Female, White, Widowed
Husband - John B. Turner
Born Caledonia, Racine County Wisconsin
Father - William McCullough, born Westchester County NY
Mother Anna Johnstone, born NY
Informant, Records, Old People's home
Undertaker - W T Rigdon Company
Cemetery - City View

Martha Burkhard
Born November 18, 1861
Died June 17, 1943 1625 Center Street, Salem OR
Born Caledonia, Racine Co. Wisc.
Father Wm. McCullough, born Westchester Co. NY
Mother Ann Johnstone, born NY
Burial City View Cemetery

I looked up death records for a John Turner, but there were too many to look up each individual record.

I can scan the death records and email them to you if you write to me at widdis77777(at)hotmail.com

Also, in the Oregon Marriage records for 1910, there was an Anna McCullough who married in Crook County. I looked in the Crook County records for 1910, but didn't find her.