Pine Shakes

Doing an inspection tomorrow on a bunalow built in 1997. Has original roof. Pine shakes. When asked, the buyers weren’t sure if they were treated or untreated. I know about the untreated but want info for these people about treated shakes and maintenance programs available.
Does anyone have a good link to this information.
As always thanks guys.

Chris,Thanks so much.
I will include in my report as links for them as well.