The area in red represents the clear space required for the tent.
(20 feet long by 20 feet wide or 400 square feet).
The area in yellow represents the clear area needed for the ropes and stakes,(ropes extent three to five feet from tent).
The green area in the picture represents the areas that can contain trees shrubs and other obstacles.
Note: Trees in the green area can not have branches that hang over the red tent area unless they are at lest 12 feet above the ground.
The ideal amount of clear space would be a 30ft wide by 30 ft long square area.