Creating a trigger that fires when a new node is created with a specific taxonomy term

I'm working on a site where I need different roles to be asked to approve a new node, depending on which term the node is tagged with. I'm using Actions 5.x-2.5 and Workflow 5.x-2.2 to set up the workflow.

I think that I have to write a trigger to fire based on the terms assigned to a new node. Has anyone done something similar and would be able to provide some guidance?

I know that there is a Taxonomy Actions module, but it doesn't quite seem to be appropriate here because it apparently defines taxonomy actions rather than triggers. (Also, I haven't managed to get it to actually show up anywhere in the Actions and Triggers setup pages, but that's probably just me.)