S.D. Codified Laws § 21-47-11
If it shall appear that the mortgaged premises can be sold in parcels without injury to the interests of the parties, the decree must direct so much of the mortgaged premises to be sold as will be sufficient to pay the amount then due on such mortgage, with costs, and such judgment or decree shall remain as security for any subsequent default. In such case if there shall be any default subsequent to such judgment or decree, in the payment of any portion or installment of the principal, or of any interest due upon such mortgage, the court may, upon the application of the plaintiff, by a further order founded upon such first judgment or decree, direct the sale of so much of the mortgaged premises to be made, under such decree, as will be sufficient to satisfy the amount so due, with costs of the application and the subsequent proceeding thereon; and the same proceedings may be had as often as a default happens.
SDCL 21-47-11