Further, T.C.A. § 64-1212 provides that a waiver of such a lien must be in writing and even then the one who purchases crops from the tenant by check must make the check payable jointly to the tenant and to the landlord. It has been noted that this section gives protection to both the purchaser and the landlord, First Citizens Nat. Bk. v. Cottonseed Products Co., 11 Tenn. App. 269 (1930), and we think that this section clearly places the burden upon the purchaser of crops to determine whether he is dealing with a tenant when it issues a check for crops. Along this same line, the United States argues that the proof shows that there is traditionally in Western Tennessee a distinction for lien purposes between a lease for cash rent and one for crop rent.