This cemetery is the Black Section of Georgetown Cemetery, it is located across the street, most of it is unmarked, though some metal funeral home markers are there they are unreadable. 
The present visible section is inclosed in chain link fencing and is a modern addition to what probably was a quite large cemetery. 
It is noted as Negro Pottsboro and Negro Georgetown in death records.
As well as just plain Georgetown Cemetery.
I found the article at the bottom of the page which tells of the burial of Andy Rice here and also tells us when the cemetery was established.
 
 

Bennett, Samuel P.       23 Jul 1876 - 15 Aug 1938 
Morrison, Charley             15 Sep 1855 - 13 Jun 1935
Ring, Deller                           11 Oc 1874 - 31 Dec 1917

Brown family plot 

Brown, Josephine  July 24 1874 - Dec 23 1941  |
Brown, William   June 15 1866 - June 20 1964 
 children: Luther, Charlie, Hassell, Aaron, Monroe 

Brown, Aaron          17 Sep 1896 - 13 Mar 1962 
Brown, Charlie       10 Oct 1905 - 14 Aug 1948
Brown, Inf of Monroe   29 April 1940 - 5 May 1940
Brown, Luther          no date - 12 Nov 1918
Brown, William       15 Jun 1886 - 20 Jun 1964
 
 

Johnson plot

Johnson, Myrtle    29 Apr 1886 - 3 July 1975
Johnson, Jack    15 Oct 1884 - 15 Apr 1958
 
 

Though this article is 'tacky' to say the least it does give us the info 
on when the cemetery was established and that he is buried here. 
I wish someone had bought him a tombstone. 
There might have been one at one time but nothing is there now.
Dallas Morning News
30 Aug 1904