There was a combined $25 million of land for sale in Decatur County recently on Land.com. The total size of all Decatur County farms, ranches, hunting land and other land for sale was nearly 3,000 acres. Decatur County ranks 46th out of 99 counties in the Hawkeye State for the total acreage of land currently advertised for sale. Of all locations in Decatur County with farms, ranches, hunting land and other land for sale, Lamoni had the most land for sale. Decatur County is Iowa's 66th largest county (533 square miles). It's located in the Central Iowa region of Iowa.