A township in the United States refers to a small geographic area, ranging in size from 6 to 54 square miles (15.6 km² to 140.4 km²), with 36 square miles (93 km²) being the norm.
The township government is a local unit of government, originally rural in application. They are geographic and political subdivisions of a county. The township is identified by a name, such as Washington Township. The responsibilities and the form of the township government is specified by the state legislature.
The most common form of township government has an elected board of trustees or supervisors. Some additional offices, such as Clerk or Constable, may also be elected. The most common responsibilities include such things as road maintenance, land use planning, and trash collection.
In most midwestern states, a civil township often corresponds to a single survey township, but in many cases, especially in less populated areas, the civil township may be made up of all or portions of several survey townships. In areas where there are natural features such as a lakeshore or large river, the civil township boundaries may follow the geographic features rather than the survey township. Municipalities such as cities may incorporate or annex land in a township, which is then generally removed from township government (although this varies--Indiana is the only state where every portion of the state is part of a township government, regardless of other municipalities, while in other states, some types of municipalities like villages remain a part of the township while cities are not. As urban areas expand, a civil township may entirely disappear—see, for example, Mill Creek Township, Hamilton County, Ohio. In other expanding urban areas, the township may incorporate itself into a city; this can be seen in the numerous square cities of Hennepin County, Minnesota.
Pennsylvania and New Jersey are different; these states have civil townships that are not based on the PLSS survey system, but on the older Metes and bounds survey system. A New Jersey township differs only in name from other municipalities: its boundaries are fixed, it is an incorporated body, and it is free to adopt another form of government. The Federal Government has frequently failed to allow for this; some New Jersey municipalities, such as the Township of the Borough of Verona or Township of South Orange Village , changed their names to qualify for additional Federal aid.