 Plunketts Creek Township was originally much larger than it is now , and two other townships were formed from parts of it . When Sullivan County was formed from Lycoming County on March 15 , 1847 , Plunketts Creek Township was divided between the counties , with each having a township of the same name . This led to some confusion and in 1856 the citizens of Sullivan County petitioned the state legislature to change the name of their Plunketts Creek Township to Hillsgrove Township , for Hillsgrove , the main village and post office in the township . In 1866 , Cascade Township was formed from parts of Hepburn and Plunketts Creek Townships in Lycoming County . 
