Bump to this. It was very weird to realize there is no list of what can be turned in to be found someplace that is easy for our characters to access. Like in oh... the Gathering and Fishing Log. Crafting doesn't have this problem as their Collectables have a nice section all to themselves in the Crafting Log. It feels like an oversight that Gatherers didn't get something similar.

Currently, the only way to find out what can be turned in and what can't be turned in is to go to one of the Collectable Appraisers and copy down the list they have to some other 3rd party tool so it can be accessed anywhere in the game. That seems... very unwieldy and very counter-intuitive. For old players, this might seem obvious (or they might have the list memorized). For new players... I can see them being very confused about where they are supposed to find out what the Gathering Collectables are.