Police say they've found suspected marijuana plants at a University of Michigan botanical garden for the second time this year.

The Ann Arbor News reports campus police on Wednesday yanked five plants out of a wooded area at the Matthaei Botanical Gardens.

Volunteers at the gardens in Ann Arbor Township, near the school's main Ann Arbor campus, had reported the plants to police.

In February, 11 suspected marijuana plants were discovered in a garden greenhouse intermixed with plants from a biology research project.

University of Michigan police Lt. Bob Neumann says he doesn't believe the incidents are related.