Cushing is a city in Woodbury County, Iowa, United States. It is part of the Sioux City, IA–NE–SD Metropolitan Statistical Area. The population …Cushing is a city in Woodbury County, Iowa, United States. It is part of the Sioux City, IA–NE–SD Metropolitan Statistical Area. The population was 230 at the time of the 2020 census. A post office called Cushing has been in operation since 1883. The city was named for L. Cushing Kimball, brother of a railroad official.