Not sure if it was intended or not, but the Tall Grass->Next combo type does not seem to have an item drop set associated with it. This is true up to beta 1337- don't know about the latest beta.
Tall Grass->Next bug
It would be more convenient if we had Tall Grass, Bush, and Flowers combo types that don't spawn items with all the ones that spawn items renamed Tall Grass (Item), Bush (Item), and Flowers (Item), since we have that kind of stuff for the Slash Combo Types. Also, I wonder why they still have not added any Flowers->Next combo types.
And now this combo type spawns items.