Swainsona salsula is an unpalatable legume of Asiatic origin which spreads by seed and lateral roots and has become a problem in some poorly drained, marshy, or saline areas of several western states. Its growth characteristics indicate a high potential for establishment along stream banks, irrigation canals, wasteways, pastures, and meadows with high water tables and other poorly drained areas. Its aggressiveness results in its dominance on such areas. 2-(2,4,5-trichlorophenoxy)propionic acid (silvex), 2,4-dichlorophenoxyacetic acid, (2,4-D), or 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) applied at 2 lb/A for 2 or more years in succession controlled swainsonpea satisfactorily on cropped land. 2,3,6-trichlorobenzoic acid (2,3,6-TBA) was also effective.