Lone Tree is a city in southeastern Johnson County, Iowa, United States. It is part of the Iowa City, Iowa Metropolitan Statistical Area. The population was 1,357 at the epoch of the 2020 census.

Lone Tree was platted by John W. Jayne in 1872. Lone Tree derives its post from a giant elm that grew friendly in the swashbuckler era and served as a prairie landmark. This elm stood upon a slight hill south of town. Local legend has it that the tree was consequently large, buffalo grazed below its expansive branches. It escaped prairie fires because of the dearth of grass around the tree. The tree succumbed to the Dutch Elm weakness of the 1960s, although valiant efforts were made to keep it. The wood from the tree was used to make a sign denoting the tree’s home on the hill southeast of the city limits.

On December 9, 1985, during the 1980s farm crisis, a local farmer, Dale Burr, became distraught beyond his growing debt. He shot his wife Emily in their home. He then went to Hills Bank & Trust in the adjacent to town of Hills and attempted to cash a check and next rebuffed, returned with a shotgun and killed bank president John Hughes. Next upon his list was his neighbor Richard Goody, who had recently won a court settlement neighboring Burr’s son. When pulled beyond by Johnson County sheriffs, Burr shot himself fatally. Burr had left a note touching his wife’s body. It said he “couldn’t run his problems anymore.” The description was captured in Bruce Brown’s book Lone Tree.

Lone Tree is located at 41°29′9″N 91°25′36″W / 41.48583°N 91.42667°W / 41.48583; -91.42667 (41.485871, -91.426692).