Township categories for US states are not all set up. If you need to add one, the format is [[Category:XXXTownship, XXXCounty, XXXState]] so [[Category:Jefferson Township, Allen County, Indiana]]. Michigan and New Jersey have charter townships and those have the same set up, but add the word Charter. [[Category:XXXCharter Township, XXXCounty,XXXState]].
Thank you, Lindy!