FWIW
We have used iron phosphate based slug bait successfully.
We've also used barriers of different types.
'because I like Lee Valley (check out their garden tools too)
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?p=58897&cat=2,51555
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?p=70633&cat=2,51555 and some info from university extension programs...
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And in the interests of online research...
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the search criteria below and paste into the search field.
domain:edu +slugs +garden +problem
(note the lack of a space between the colon and 'edu')
The search is limited exclusively to the .edu domain and eliminates the diy 'about' and 'how to' and commercial sites. -- Alternately, you can use the advanced search page.