In this case, the river was named by early French explorers for a different root vegetable, the potato-like prairie turnip (Pediomelum esculentum, syn.

It flows into Marsh Lake on the Minnesota River in southwestern Swift County, approximately four miles (6 km) southwest of Appleton.

Marsh Lake was formed by a backup of water caused by the Pomme de Terre's delta, and is presently maintained by a manmade dam.

Downstream of Morris, the river flows on till plains between eroding banks and becomes increasingly turbid.

According to the Minnesota Pollution Control Agency, approximately 81% of the land in the Pomme de Terre River's watershed is used for agriculture; of this area, half is used for the cultivation of corn and soybeans, and 43% for that of hay and small grains.