For the gathering log for level 1-5 botanists, several of the items are listed as being found in areas that, according to the log, are 30-50. I haven't gone to double check or to see if there is a safe route for gathering, but some of the names i recognize are definitely higher level areas. Also, the areas are all over the world, unlike hunting logs which have you hunting in one world area, at least at lower tiers. It makes it quite hard to finish the gathering log and get the associated experience.