Rough zones are turf zones in rugged terrain that cannot be taken without extra effort, due to topographically or terrain-difficult obstacles.
In swedish "mullezoner" mulle is derived from skogsmulle (forest mulle) and skogsmulleskola (forest mulle school), where children around preschool age stay in a forest environment and learn things about nature. The word mull is the base.
In Turf, "mullezoner" or Rough zones refers to a zone in such an environment that it requires an extra effort to take.
“This is "Skogsmulle"
Skogsmulle is an imaginary figure, a creature of its very own kind, who was born in a thunderstorm from completely natural ingredients. Skogsmulle is one with the forest, he loves and defends nature, often with the help of the children. In the children's imagination, Skogsmulle is a good and creative force, not because of any supernatural forces, but because he defends what grows and lives. ”