Just to add to Terraferminator's solution. The four Knothole surprises in the graveyard in his solution are spot on.
There are 2 more however:
-One is in the first area of Bog Easy (the area with the shop where you enter through the roof). If you look across the water in front of the buildings, there is a tree slightly to the left. Thin that out for a 5th Knothole surprise
-Another is next to the Jugband (the machine with instruments on it that you can decide to Salvage or Destroy in a quest) in the 2nd area of Bog Easy. It is a tree to the right of the Jugband. Thin this out for the 6th and final Knothole Surprise.
Hope that helps. Thanks