For your airplane:

three pieces of 1" thick plywood (one for each wheel)

12" or 18" square

Shut down your engine a foot or two short of the line, place the squares
ahead of the wheels and pull the airplane up onto the squares.

These will keep your wheels from sinking into the soil while you are
there, making your departure much easier, rolling off the plywood
instead of pulling your airplane out of the holes.