Individual item collision from a list?

[SpecOpsSammich]

I'm making a lawn mowing game that has the player run over 30 ferns to clear a field in 3 minutes, and im having trouble getting the lawnmower interact with the ferns from a list. I have:
For all ferns in list, every ferns in list
If lawnmower distance to items from fernList < 2
then increment world scoreSet by 1
and fern turns invisible
Else nothing
I believe the error is the If part, trying to get the lawnmower to interact with all items from the list, then trying to get the individual item in the list to disappear. Is there an easier way to accomplish this? please help.

If it helps i attatched the world