Beware of Poison Ivy, Poison Sumac, and Other Toxic Plants in Michigan

Toxic Weeds in Michigan to Watch Out For

Michigan's forests, fields, and landscapes are home to a wide variety of plant life. While most are harmless, there are some toxic weeds and plants in Michigan that can cause skin irritation, rashes, and other health issues. Being able to identify these dangerous plants is crucial, especially if you plan to hike, camp, or spend time outdoors in Michigan.

Poison Ivy

Poison ivy is one of the most well-known toxic plants in Michigan and other parts of North America. This infamous weed contains an oily resin called urushiol that causes an itchy, blistering rash in most people. The rash develops 12 to 72 hours after exposure and can last for a few weeks. Poison ivy grows as a vine or ground cover and has three glossy, pointed leaves. The leaves can be reddish or green depending on the time of year. Poison ivy is commonly found in forests, fields, along trails, and in suburban areas.

Poison Sumac

Poison sumac is a woody shrub that also contains urushiol and causes a rash similar to poison ivy. This plant has 7-13 leaflets per stem that are elliptical in shape and green in color. Poison sumac grows exclusively in very wet areas like swamps, bogs, and peatlands. Be on the lookout for this toxic plant if exploring marshy areas in Michigan.

Poison Oak

Poison oak is less common than poison ivy in Michigan but is another plant to avoid. Like its relatives, poison oak contains urushiol and causes blistering rashes in most people. Poison oak has lobed or toothed leaves that resemble oak leaves. It can grow as a shrub or vine. Poison oak favors dry, sandy soils and is most often found in southern Lower Michigan.

Cow Parsnip

Cow parsnip is a tall, flowering weed that can reach up to 6 feet in height. This plant has large leaves and umbrella-shaped clusters of small white flowers. Cow parsnip contains chemicals called furanocoumarins that can cause blistering rashes if skin is exposed to sunlight after contact with the plant. The sap of cow parsnip can also irritate the skin. Be cautious of this towering weed when hiking or doing fieldwork in sunny locations.

Wild Parsnip

Wild parsnip is an invasive weed from Europe that has spread throughout Michigan. Like cow parsnip, this yellow-flowered plant contains chemicals that react with UV rays from the sun to cause severe burns and blisters on the skin. The rash can develop hours after exposure and leave behind discolored patches on the skin. Wild parsnip has yellow flowers similar to the cultivated vegetable parsnip and typically grows 2-5 feet tall.

Wood Nettle

The wood nettle plant looks very similar to stinging nettle but favors drier, woodland settings. True to its name, wood nettle is covered in stinging hairs that contain chemicals like histamine, acetylcholine, and formic acid. Brushing against this plant results in a painful, burning rash that can last for several hours. Wood nettle has oval shaped leaves with serrated edges and tiny greenish flowers. It grows 1-3 feet tall in forests throughout Michigan.

Stinging Nettle

Stinging nettle is very common in Michigan and notorious for the stinging and irritation it can cause when touched. Like wood nettle, stinging nettle has needle-like hairs on its leaves and stems that release chemicals resulting in pain, swelling, and redness. Stinging nettle grows in moist soils along trails, fields, and disturbed areas. It has heart or oval shaped leaves with toothed edges and tiny green flowers.

Bull Nettle

Bull nettle is a wild edible plant that paradoxically can also sting you. This member of the nettle family lacks stinging hairs but the leaf shape and veining causes mechanical irritation and blistering of the skin. Bull nettle has cordate, sandpaper-like leaves with finely toothed edges and tiny green flowers. It grows in partially shady areas like woodlands and thickets.

Spurge Nettle

Spurge nettle is a uniquely toxic plant in the nettle family. Instead of stinging hairs, spurge nettle secretes a milky, irritating sap when leaves are damaged. This sap contains chemicals that can severely blister skin and damage eyes. Spurge nettle has alternate oval leaves with smooth or slightly toothed edges. Tiny green flowers emerge from the leaf axils. This dangerous plant grows in woodlands and floodplains.

Giant Hogweed

Giant hogweed is an extremely toxic plant that can grow up to 14 feet tall. This invasive weed has thick, hollow stems with purple blotches and large lobed leaves up to 5 feet wide. The sap of giant hogweed contains furanocoumarins that cause phytophotodermatitis when reacted with sunlight. This results in painful burns, blisters, and scarring. Touching giant hogweed and exposing skin to sun can lead to permanent blindness. Report any sightings of this dangerous plant to state authorities.

Wild Chervil

Wild chervil is a flowering weed which resembles the cultivated herb chervil. Like its relatives in the carrot family, wild chervil contains furanocoumarins that can cause skin irritation when exposed to UV light. The leaves, stems, and roots of wild chervil can all cause a reaction. This toxic weed has lacy, fern-like leaves and white flower umbels. It grows in meadows, fields, and roadsides throughout Michigan.

Water Hemlock

Water hemlock is an extremely poisonous plant that grows in wet areas like marshes, swamps, and creek banks. This weed has umbrella-shaped clusters of small white flowers and fern-like leaves with toothed leaflets. All parts of water hemlock contain the toxin cicutoxin which affects the central nervous system. Consuming water hemlock can be fatal. This dangerous plant should not be touched or eaten.

How to Protect Yourself from Toxic Plants

While Michigan’s wilderness offers beauty and adventure, you need to be cautious of plants that can harm you. Here are some tips to avoid injury and irritation from toxic weeds and plants:

• Learn how to identify dangerous plants before heading into nature. Knowing what poison ivy, poison sumac, hogweed and other toxic plants look like can help you steer clear of them.
• Wear protective clothing like long pants and sleeves when hiking or doing field work.
• Stay on designated trails when possible and avoid brushing against plants.
• Don’t burn or mow over toxic weeds as this can spread irritants in the smoke or debris.
• Wash skin and clothes if you come in contact with sap, leaves or stems of toxic plants.
• Apply barrier creams or lotions before exposure to irritating plants.
• Recognize the early symptoms of a toxic plant reaction like redness, itching, and swelling.
• See a doctor for severe rashes, blisters, or reactions to properly treat exposure and avoid complications.

First Aid for Toxic Plant Exposure

If you accidentally touch, brush up against, or are exposed to a dangerous plant in Michigan, follow these first aid tips:

• Wash the affected skin with soap and cool water immediately to remove plant oils and sap.
• Apply a paste of baking soda and water to soothe itching and inflammation.
• Use over-the-counter hydrocortisone cream to relieve swelling, blistering, and redness.
• Take an oral antihistamine containing diphenhydramine to reduce body’s allergic-like reaction.
• Soak in a colloidal oatmeal bath for widespread rashes to ease itching.
• Use cold compresses on skin to relieve discomfort from rashes and blisters.
• Avoid scratching as this can spread the reaction and cause infections.
• See a doctor if rash covers large parts of the body, swelling worsens, or other concerning symptoms develop.

Prevent Toxic Plants From Growing Near Your Home

To reduce encounters with dangerous plants, discourage them from growing on your own property by:

• Removing any poison ivy, poison oak, or poison sumac already growing near your house or yard.
• Wear protective clothing and discard parts in sealed bags to prevent exposure during removal.
• Applying concentrated herbicide to weeds you want to kill.
• Planting native groundcovers and shrubs around your yard to prevent colonization of unwanted weeds.
• Laying down mulch or landscape fabric to block toxic plants from germinating.
• Maintaining healthy turf and landscaping that outcompetes undesirable weeds.
• Avoiding composting toxic plants as this can spread seeds and oils.

Control and Remove Toxic Weeds Safely

If you have poison ivy, poison oak, wild parsnip or other dangerous weeds on your property, use caution when attempting to get rid of them. Here are some tips for safely controlling and removing toxic plants:

• Wear protective clothing including gloves, long sleeves, pants, and eyewear.
• Carefully spray plant leaves with an herbicide like glyphosate, triclopyr, or 2,4-D.
• Cut large plants at ground level with pruning shears or a brush cutter.
• Use a shovel to dig up small plants by the roots to prevent regrowth.
• Bag and seal plant parts to prevent contact during disposal.
• Power wash any tools, gloves, and boots used when finished.
• Monitor area and spot treat any regrowth.
• Replant area with non-toxic, native groundcovers.

Teach Children to Recognize and Avoid Harmful Plants

Kids love playing and exploring outdoors but may not be aware of dangerous plants lurking in woods and fields. Teach children to be cautious of toxic weeds by:

• Showing them photos and descriptions of poison ivy, poison oak, poison sumac, and other irritating plants.
• Pointing out identifying features like leaf arrangement, edges, flowers, and growth habit.
• Explaining painful rashes and other effects from touching certain plants.
• Encouraging them not to touch, rub, or eat any plant unless an adult says its ok.
• Keeping kids on trails and away from dense brush when hiking.
• Having kids wear long pants and sleeves when playing outside.
• Instructing children to immediately tell an adult if they touch a plant that causes itching, stinging, or other odd sensation.

Understanding how to identify toxic plants, prevent exposure, and treat reactions can help you safely enjoy Michigan’s beautiful outdoor spaces. Be vigilant of poison ivy, poison oak, giant hogweed and other dangerous plants when adventuring in the Great Lakes State.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.