I've dug out figures that show that by 1860 it took 1 slave to tend 10  
acres of most crops. Recognizing that coerced labor is what it is, are  
there also figures on what subsistence farmers were able to do on  
average with their crops on a comparable basis.

Did no-one in the ante-bellum US do studies on agricultural  
productivity for slave and free labor, possibly abolitionists? I've  
been working on agri-techno-changes and would like some form of  
comparative basis to flesh out the lectures.

Thanks in advance.

Lyle Browning