That's kinda hard when you hit a point where everything costs no less than $6,000,000 each.
Not 100% covered in them, space the land mines out a bit. Same for launchers, and it'll never end.

The mines are spaced so close that when you hit a turtle it sets one off then that one sets the others off.
Basically it sends every turtle on the floor at the time flying.
I had to Manuely stop it to get a picture.
EDIT: 