I believe I am a descendant of William John Plog, who was probably my great, great, great grandfather. My grandfather, Frederick Thomas Plog, was from the Pougkeepsie, NY area and settled in New York City (Manhattan). He had four sons with his wife, Anna B. Davis: Frederick Thomas Plog, Jr., Charles William Plog, Henry J. Plog (my father), and Joseph J. Plog. My father and uncles used to speak of an "Uncle Willie"--I think their granduncle--who was caretaker for over 50 years at FDR's estate at Hyde Park. They mentioned visiting their uncle and Plog cousins at Hyde Park as boys in the '30s. My grandfather and grandmother are buried in the Plog section of a cemetery at Peekskill NY, along the Hudson. Some of their "Ludwig" cousins are buried there, too.
I have been in touch with Janice Plog Dennis and Bill Plog Hahn who posted followups on this site. I would very much appreciate hearing from any other person who might shed light on my Plog ancestry.