The mine planter was transferred to the U.S. Navy in March 1951 to become an Auxiliary Minelayer (ACM / MMA) under naval designation. She was then berthed at Boston as a unit of the Atlantic Reserve Fleet. While in the Reserve Fleet, she was redesignated MMA-14, 7 February 1955, and named Monadnock, 1 May 1955; the second ACM to bear this name. The ship was never commissioned and thus never bore the "USS" prefix. Monadnock was struck from the Navy list on 1 July 1960 and sold to commercial interests. In commercial service the ship was named Thiti, Amazonia and eventually Dear operating into the 1980s under Italian registry.