What type of sod were sod houses made of?

The sod homes of those who settled on the midwestern prairies were made from the prairie itself. Settlers in the Dakotas, Minnesota, Nebraska, Kansas, eastern Colorado, and eastern Wyoming, where trees were scarce, dug their homes into the earth. Usually a sod home was dug out of a hillside as temporary quarters until the family had the time, supplies, or money to build a cabin or wood-frame home. Some Native Americans also built sod dwellings. By 1890, sod homes were becoming a rarity on the plains. If you’d like to experience one firsthand, Hayes County, Nebraska, claims to have three sod homes suitable for living.