Northern Michigan University is warning students they could face a $25 fine for hanging a hammock on trees in the city of Marquette.
WLUC-TV reports hammocks are allowed on the school's Marquette campus. But a letter from the Upper Peninsula school says the city asked the school to make people aware that hammocks have been causing tree damage in public areas, such as Presque Isle Park.
The warning notes that using screws to put up hammocks can cause trees to break or contract diseases. People are encouraged to use hammocks that don't damage trees.
Students, faculty and staff have been warned that police in Marquette plan to step up enforcement of rules that prohibit attaching rope, wire, nails or signs to trees.
Tickets start at a $25 civil infraction.
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