Last Friday, Northern Michigan University professor Taimur Cleary decided to take his lecture outside of the classroom.

He and 12 students packed up their things, went to nearby Presque Isle Park and worked for hours on an art installation.

The result? Layers of autumn leaves covering puddles in between the park's rocky cliffs, known as Black Rocks.

Cleary, who teaches painting and drawing at the Marquette university, said he came up with the idea from a movement called Earth Art. Starting in the United States in the late 1960s, the art form uses natural landscapes to create installations on-site.

Materials from nature are often used, such as rocks, soil, water, or in Cleary's case-- leaves. He said he was directly influenced by British artist Andy Goldsworthy, who likes to arrange branches, leaves and rocks in lines, circles, spirals, or holes in his artwork.

Cleary chose Black Rocks as the site because of its "unique geology."

"These extremely old, billions of years-old rocks are punished every winter by ice, wind and waves," he said. "So nothing really grows there, they're just these large, dark-colored rocks without any trees around them. By bringing the leaves from other places and putting them there, they stand out more."

"It's a pretty special place and has been for a long time for a lot of people, so we were glad to be a part of that for a minute."

Cleary said the project was planned on short notice. The 12 students volunteered for a demonstration session, where the professor gave a short lecture on Earth Art and then they hit the outdoors. They spent about 45 minutes collecting thousands of leaves before heading to Black Rocks. By 3 p.m., Cleary and the students had completed the project.

"We had a lot of fun, even after making the work, just sitting back where people couldn't tell we made it and watching them come up, discover it and be surprised" he said. "People couldn't figure out what it was for and a lot of people asked us questions on why we were making it. Hopefully it changes the way people engage and look at the landscape."

Cleary has done similar art installations with students in the past. Last year, they used stones from Black Rocks and arranged them in a linear pattern, and in 2016, a different group worked on the leaf project.

This year's project has become popular on social media, as a Facebook post received 1,000 shares, more than 800 reactions and almost 200 comments on NMU's Earth Art page.

During the winter, Cleary is hoping to create his next installation made out of snow. He said, earth art is like the weather; it changes often.

"That's how nature is, that's how everything is," Cleary said. "Hopefully it makes people think about time differently."

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