Translation:Shulchan Aruch/Choshen Mishpat/328

Paragraph 1- If one accepts a field from another and it does not produce appropriately but produced two seah more than the expenses, the renter is required to work with it because he wrote to the owner, “I will stand and plant . . . and I will establish a pile for you and you will take your portion etc.” Even if he did not write this it is as if he wrote it.

Paragraph 2- If the renter did not work the field and let all or some of it lie fallow, we would appraise how much the field was expected to produce, and he must give the portion the owner should have received. If the renter made a condition that if he lets the field lie fallow and does not work it then he will give 1,000 zuz, it is an asmachta and he is only required to pay the amount that the field should have produced.