If any tract of land is sold, as provided, for the collection of the assessment, the clerk of the court having cognizance of such cause shall certify to the clerk of the county, where the suit establishing the drainage district was instituted, a copy of the decree, and the decree shall be entered on the drainage record book in the office, and filed with the papers in the cause; and the county clerk shall certify this decree to the trustee charged with the collection of the assessments, who shall enter the change of owner and other changes shown in the decree, on the drainage assessment book, and thereafter collect the assessments accordingly.