N.C. Gen. Stat. § 156-58
If, at the time of the filing of the petition, or at any time subsequent thereto, it shall be made to appear to the court by affidavit or otherwise that the names of the owners of the whole or any share of any tracts of land are unknown, and cannot after due diligence be ascertained by the petitioners, the court shall order a notice in the nature of a summons to be given to all such persons by a publication of the petition, or of the substance thereof, and describing generally the tracts of land as to which the owners are unknown, with the order of the court thereon, in some newspaper published in the county wherein the land is located, or in some other county if no newspaper shall be published in the first-named county, which newspaper shall be designated in the order of the court, and a copy of such publication shall be also posted in at least three conspicuous places within the boundaries of the proposed district, and at the courthouse door of the county. Such publication in a newspaper and by posting shall be made for a period of four weeks. After the time of publication shall have expired, if no person claiming and asserting title to the tracts of land and entitled to notice shall appear, the court in its discretion may appoint some disinterested person to represent the unknown owners of such lands, and thereupon the court shall assume jurisdiction of the tracts of land and shall adjudicate as to such lands to the same extent as if the true owners were present and represented, and shall proceed against the land itself. If at any time during the pendency of the drainage proceeding the true owners of the lands shall appear in person, they may be made parties defendant of their own motion and without the necessity of personal service, and shall thereafter be considered as parties to the proceeding; but they shall have no right to except to or appeal from any order or judgment theretofore rendered, as to which the time for filing exceptions on notice shall have expired.
N.C. Gen. Stat. § 156-58