Place
- Oceana1
- Ogemaw1
- On Galien River. Warren Woods State Park [ca. 4 miles east of Union Pier].1
- On the south bank of Big Murphy Creek, just east of county road 437.1
- Ontonagon.1
- Oscoda1
- Ottawa National Forest, Bessemer Ranger district (C32 stand 3). T48N R46W section 23, NWNE. Between Sapsucker Creek and Montowibo Creek.1
- Ouray1
- Owosso1
- Pikes Peak1
- Pleasantview Twp., ca. 5.5 mi. W. of Brutus.1
- Port Huron1
- Prentiss Bay.1
- Presque Isle Twp. About ¼ mi. W. of shore of Lake Huron.1
- Pte. Mouillee State Game Area.1
- Reese's Bog.1
- Rensselaer1
- Riverton Twp., ca. 3.5 mi. SW of Scottville.1
- Rochester.1
- Roscommon1