I only see Joseph listed on the 1900 census, one son list his fathers name as Edgar not Joseph so maybe looking for a Joseph Edgar Blackston or Blackstone, one son listed on death certificate as last name Blaxton, by the time the 1910 census was out his wife Janie Blackston was head of house.
I do see a Blackiston-32 Joseph Blackstone on a 1860 census listed his birth as Maryland