Chris and Mobirders -
I have used mouthwash as a tick and
chigger deterrent for a couple of summers now.  Great success! 
Try it.  Environmentally safe too as far as I know.
I have a spray plastic bottle in the trunk that I carry all of the time.
Good birding,  Larry Herbert, Joplin MO.
The Audubon Society of Missouri's Wild Bird Discussion Forum
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