Example. A, a farmer, needs money in order to harvest his crop. However, a Federal tax lien, notice of which has been filed, is outstanding with respect to A's property. B, a lending institution is willing to make the necessary loan if the loan is secured by a first mortgage on the farm which is prior to the Federal tax lien. Upon examination, the district director believes that ultimately the amount realizable from A's property will be increased and the collection of the tax liability will be facilitated by the availability of cash when the crop is harvested and sold. In this case, the district director may, in his discretion, subordinate the tax lien on the farm to the mortgage securing the crop harvesting loan.
26 C.F.R. §400.2-1