to the tenant in said lease contracts which embarrass him or her in earning the stipulated money rental, for failure to comply with which a further money payment per acre is charged as rent. It is expressly provided in said lease contracts that the tenant shall not allow grain stalks grown on the land to be eaten by the tenants' animals, the landlord reserving such grain stalks to himself or herself; and as a further burden on the tenant and as a further security to the landlord the tenants are made to waive the benefit of the exemption, valuation and appraisement laws of the state.