The Department of Natural Resources is trying to make sure invasive species don't penetrate one of Minnesota's most popular state parks.

The DNR announced Monday it will be inspecting all watercraft that enter Itasca State Park starting Friday – the weekend that kicks off the unofficial start to summer and that state's boating season.

The iconic park, which is home to the headwaters of the Mississippi River, is one of the state's most-visited, MPR News notes.

“The lakes and waters of Itasca State Park are precious resources,” Chris Gronewold, Itasca State Park resource specialist, said a news release. “Our visitors have a stake in preventing the spread of aquatic invasive species in park waters, as well as all waters in the state.”

The DNR hopes to prevent invasive species from entering the park's waterways. Inspectors will make sure visitors are following state law, which requires boaters to clean weeds and debris off their boats, remove drain plugs and keep them out while traveling, and dispose of unused bait in the trash.

Any boaters that don't comply to the law may be denied access, the DNR notes.

Difficult to control

Invasive species, like zebra mussels, Eurasian watermilfoil and spiny waterfleas, can easily be carried from lake to lake on aquatic plants that are left on a boat or trailer. If they enter a lake, their population can increase rapidly, hurting the health of the water. They can also be harmful to humans.

There are some methods that have helped control invasive species, but it has been difficult to completely get rid of them.

The DNR has been dealing with the spread of invasive species in numerous Minnesota lakes in recent years. MPR News says more than 175 lakes and rivers are infested with zebra mussels.

To prevent the spread, the DNR recommends boaters spray the boat with high pressure water, rinse it with hot water, or dry the boat and equipment for at least five days.