Giant hogweed can grow up to 12 feet tall in Michigan and causes serious skin irritation if touched. The United States Department of Agriculture is requesting that anyone who encounters this plant report it. Here, Mike Zeller of the Animal Plant Health Inspection Service-Plant Protection Quarantine (APHIS-PPQ) poses next to an example of giant hogweed in Pennsylvania. (Photograph courtesy of the United States Department of Agriculture) Early summer concerns that a massive plant called giant hogweed, which can cause a painful and lasting skin rash, has sprung up near Pte. Aux Chenes has been identified as a benign look-alike called cow parsnip.

Linda Swartz, a botanist for the East Unit of the Hiawatha National Forest, investigated reports from residents living on Maple Drive, near Pte. Aux Chenes Road in Moran Township, and identified the cow parsnip, possibly saving it from being uprooted by alarmed citizens.

She is on the lookout for all invasive plants, painful ones like Giant hogweed and pretty ones like purple loosestrife, and is involved in several area eradication programs this summer.

Above, left: Garlic mustard, an invasive species, is being removed from the Cut River area this summer by Linda Swartz of the U.S. Forest Service with help from an Engadine 4-H volunteer group calling themselves "The Hardcore." While the patch at Pte. Aux Chenes turned out to be the native cow parsnip, giant hogweed could still be growing in the area, Ms. Swartz said, because people plant it in their gardens. It is an attractive plant with enormous, lush, green leaves and flowers that bear a striking resemblance to the blooms of Queen Anne's lace. It can grow up to 12 feet tall in Michigan and up to 20 feet tall in southern regions.

Hogweed produces a watery sap that causes a serious skin reaction called "photodermatitis" if touched. Once skin is exposed to this sap, it sensitive to sunlight. The combination of sap and sun can cause blisters and red blotches that may become dark scars. These scars may persist for several years. Further, if the sap touches a person's eyes, it can cause blindness, according to MSU Extension.

Cow parsnip, like giant hogweed, also bears enormous, lush, green leaves and large flowers that resemble the umbrella-like Queen Anne's lace. It can also grow to be very large, up to eight feet in height.

Both plants have white hairs on their stems, but the hairs of giant hogweed are coarse, and the hairs of cow parsnip are soft. Further, giant hogweed bears noticeable purple blotches on its stem, while cow parsnip stems are green and sometimes have a slight purple tinge.

The Michigan State University (MSU) Extension office in St. Ignace provides pamphlets describing the threat of giant hogweed and common look-alikes, such as cow parsnip.

The United States Department of Agriculture (USDA) is tracking infestations of hogweed throughout Michigan and is seeking public help locating sites where the plant is growing. Anyone who has discovered this invasive plant can call the Michigan Department of Agriculture at (800) 292-3939, or Ms. Swartz at the St. Ignace District of the U.S. Forest Service at 643-7900.

As of July, 2005, the closest sightings of giant hogweed to Mackinac County were confirmed in Gogebic County, at the western Invasives end of the Upper Peninsula, and Manistee County, on the northwestern edge of the Lower Peninsula.

Above, right: This summer, an invasive species called purple loosestrife is being targeted by members of the Brevort Lake Association with help from the U.S. Forest Service. Purple loosestrife is capable of devastating wetlands. Retail sales of this plant are banned in Michigan, with the exception of cultivars bred to be sterile. Violations result in fines of $25 to $100 per offense. Sterile varieties must be approved by the director of the Michigan Department of Agriculture. (Photograph courtesy of Linda Swartz, botanist for the East Unit of the Hiawatha National Forest) Other similar plans include the safe angelica plant, wild parsnip, which can also harm skin, or the deadly poison hemlock plant.

While no giant hogweed has been found in Mackinac County, Ms. Swartz is continuing her quest to fight other invasive plants from spreading throughout the area. One is the early-blooming garlic mustard, a plant capable of shading out wildflowers and other native plants that dwell on the forest floor. It grows to be tall and bears delicate, light green leaves.

Garlic mustard, a European member of the mustard family, wreaks havoc in native plant life because it secretes chemicals that kill beneficial "arbuscular mycorrhizal fungi" that exists throughout the soil. This fungi supports the growth of tree roots, such as maples. Maple seedlings that occupy areas with garlic mustard do not develop properly.

To combat garlic mustard, Ms Swartz has enlisted the help of a volunteer 4-H group from Engadine calling themselves "The Hardcore." They will be working to extract garlic mustard Saturday, June 17, along the Cut River and at the river's mouth, where garlic mustard threatens an endangered plant called the Michigan monkey flower.

Ms. Swartz advises area residents who encounter garlic mustard plants to pull them up, bag them, and dispose of them in a way that does not allow the plant to re-seed. Throwing it into piles, she said, will allow it to re-seed, as will allowing large amounts of the plant into landfills. For further information on disposal, contact Ms. Swartz.

A second major threat to local ecological systems is a beautiful, but invasive, flower called purple loosestrife, Ms. Swartz said. This hardy plant spreads in wetlands along shorelines, in wet meadows, and in roadside ditches. Purple loosestrife forms dense stands that choke out native plants that animals depend on for summer forage, according to the USDA.

The plant has infested ditches near Brevort Lake at the corner of Knowles Road and Dukes Road. The Brevort Lake Association and Ms. Swartz are trying to eradicate the plant manually.

These efforts will take place in August as the striking purple flowers appear. Like giant hogweed, purple loosestrife is a plant brought to the from Europe as an ornamental addition to gardens. Like most invasive species, it escaped the competitive controls of its native area and is so hardy it can even fill in areas of shallow water, Ms. Swartz said.

Those interested in extracting purple loosestrife are advised to remove all pieces of the large portion of its root, because purple loosestrife is notorious for regenerating from buds on its roots.

"It is very resilient," Ms. Swartz said, "but it is important not to destroy other vegetation around it. If herbicides are used, you may wind up with more purple loosestrife than before."

Since purple loosestrife has become an ecological threat throughout the country, and eradication efforts are underway, residents should be advised not to destroy look-alikes such as swamp loosestrife, fireweed, blue vervain, or winged loosestrife, all of which bear attractive purple flowers.

There are equally attractive, environmentally friendly flowers that can be planted in gardens in place of purple loosestrife, Ms. Swartz said. These flowers include blazing star, also known as gay feather, delphinium, false spirea, lupine, lobelia, and salvia.

At left: Summer has residents on the lookout for a dangerous plant called giant hogweed, which bears enormous leaves, flowers similar to the blooms of Queen Anne's lace, and purple splotched stalks that can reach 12 feet in height. Here, Barbara Heuer of Moran Township poses next to a common look-alike called cow parsnip.