getting trapped inside a park

Towed my son`s TT to his storage spot. Had to cross an open field that looked pretty good....until......about 50 feet short of the road I would drive out on after dropping his trailer. I have a dually with 4x4. The truck and trailer bogged down in the muddy grass. Put the beast into 4 wheel drive and tried to back out of the bog....no go. Tried to go forward, no go. So we decided to drop the trailer where it was and then with much backward and forward motion I was able to free the truck from the deep ruts. Just as I turned onto the road, the owner came with his tractor. He hooked up to the trailer and moved it ahead to the storage position. The field did look good until near the storage spot. Not doing that again. My son`s truck was in the shop and that`s why I did the towing for him.