I have Clans and Landlord installed, and Landlord seems to be working somewhat, as the /lord command works.

When I place Large Banner on Pole, though, nothing happens.

I do have the crafting recipe for the Pole turned off on my server, also, but this didn't affect anything last wipe.

I've checked with the last version of Oxide and it works well. Try re-init the plugin. Remove it from the plugin directory and place it in the directory again. Make sure you have the last version of ZoneManager and Clans.