Looking at my EFP map I believe that the 7th Ward is more between Wilson, LA and the Woodland Community (off Hwy 67, north of Clinton).
I haven't been able to find out for sure where Richland Hill was, but I did notice on the map a Richland Creek in the 7th Ward, it crosses Hwy 422 (which runs in 7th ward between Hwy 67 North and Hwy 19), so I would GUESS that it was somewhere nearby.
My EFP Cemetery book says there is a Harrell Cemetery "5 miles north of Clinton on Sensley Property". (5 miles north of Clinton, up Hwy 67, would be in the 7th Ward area.
You were looking for a Jared Washington Harrell. I don't see a listing for him or his wife, V. A. Harrell, in the cemetery - BUT they might have been buried there, but by the time this list was taken down in about 1970, there was no headstone. Or maybe after their children died they moved on? Not sure. BUT their sons, Jared Furlow Harrell - age 9 & Samuel Singletary Harrell - age 1, and daughter, Josephine Emma Harrell - age 2, are listed as buried there.
Hope this helps you some...please let me know if I can do anymore digging for you.