I have Geax Saguaro 2.2" tires that clog up with our sticky red clay. This happens when it is muddy, or even when it is just a little wet. They work pretty good in other conditions - rocks, roots, dry.
My bike is a Jamis Dragon, if that matters for frame clearance.
I am looking for a tire that will work better when it's wet or muddy, and still be good for other conditions.
Land Shark, Ritchey, Fat Chance, and about 19 others
I don't really have any clay type mud in my area but I have had a lot of luck with both the neo-moto and quasi-moto tires. The quasi-moto, though a dry conditions race tire, did surprisingly well the couple times I hit serious mud. The neo-moto is my all around tire and I am quite happy with it. I run both in a 2.1 fwiw.