South Bruce OPP are investigating a single vehicle fatal crash.
It happened just before 5:30 PM on Wednesday on Concession Road 4 east of Port Elgin.
Police say it appears the 54 year old Arran Elderslie woman swerved to drive around an oncoming farm tractor, but lost control and struck a tree.
Rose Middleton was pronounced dead at the scene.
The road was closed for almost six hours for the investigation.