BIRCH/BURCH FAMILY, CLARK CO., KENTUCKY

I am looking for more information on the George Birch and Mary Polly Ogden Birch family.....they are both to have been born and died in Clark county Kentucky ca 1812-1912.
Children were James, Thomas, Henry, Amanda, Harvey, William, Mary and Warren.
George Birch's father was George Sr. and mother was Molly Unknown....1766-1850...born Virginia, died Clark co., Kentucky.
Can anyone go back on George Birch Sr.?
I thought George Sr. parents were John Burch and Mary Ann Harris of Prince George co., Maryland, but the more research I do the less I believe this, but yet I cannot find who his parents could of been.
I found the surname spelt both Birch and Burch.....any and all help would be appreciate, no matter how small.
Marie in Illinois
eebayles@msn.com