MOUNT ZION - Once you know what to look for, you can find garlic mustard all over Spitler Woods State Natural Area.

That's why Mount Zion High School students, armed with gloves and garbage bags, were in the woods Thursday. As an Earth Day project for their environmental science class, the teens pulled up all the garlic mustard they could find.

"It's all over the forest floor," said Randy Hawkins, site superintendent. "It's not native to the area, and this part, particularly back here, is a federally protected nature preserve. We're just trying to clean it up."

The project is a pilot called Earth Day in the Parks, said Mitch Ingold of the Division of Parks and Recreation. Ten state parks invited students to visit for Earth Day projects and if all goes well, the program will expand next year.

"We're asking students to come help with stewardship," Ingold said.

Garlic mustard is native to Europe and first came to this side of the Atlantic Ocean as food. The problem with the plant, Hawkins said, is that it chokes out the native plants.

Spring beauty, wild ginger, bloodroot, Dutchman's breeches and other native plants compete with garlic mustard for resources, and wildlife that depends on the native plants can suffer as a result. The chemicals in garlic mustard are apparently toxic to the eggs of the white butterfly, because the eggs fail to hatch when laid on the plant.

Employees have worked to remove the garlic mustard from the woods, but it spreads rapidly, which is one reason the students were asked to help. The pulled-up plants will be burned.

Distinguishing the garlic mustard from other plants is important. The garlic mustard produces white flowers and can be mistaken for white wildflowers.

"We're just going around, trying to find garlic mustard plants and rip them up so they won't come back," said Kylie Mitchell, a sophomore.

"They're not good for the environment," said junior Kelsey Polk. "They're just a waste of space."

Valerie Wells can be reached at vwells@ herald-review.com or 421-7982.