Know the nasties

Avoid these plants to save yourself from painful rashes, blindness – even death

|  Story by Meghan McMahon  |


The abundance of plants we have in Will County can be a sight to behold, particularly in the spring and summer months. The vibrant green combined with pops of color as various trees and flowers bloom can overwhelm the senses.

As innocent as these plants dotting the landscape may seem, not all are safe for humans or animals. Some can cause painful, burning rashes, while others may cause mild skin irritation. And while some can safely be touched, they are toxic if consumed by humans or animals. Here’s a closer look at some of the plants that can cause you harm and are best avoided.

Queen Anne's Lace

Queen Anne's lace in a field.

Queen Anne’s lace is common across Illinois, although it is not a native plant. Instead, it’s native to Europe, but was introduced to the United States by early settlers and has spread widely, according to the Illinois Department of Natural Resources.

Queen Anne’s lace, which is also known as wild carrot, has flat clusters of tiny, white flowers that create a lacy appearance, and there is usually one purplish or reddish flower at the center of each flower cluster, IDNR reports. It typically grows 2 feet to 3 feet tall, and its stems are lightly fuzzy with small grooves.

Coming into contact with Queen Anne’s lace will not cause a problem for many people, but those with sensitive skin may develop irritation or blistering, according to the U.S. Fish and Wildlife Service. Ingesting parts of the plant can be toxic for some people and animals, however. In addition, the plant looks similar to several others that can cause more serious reactions, so it’s best not to touch it unless you can be sure of what it is.

Cow parsnip

Closeup of cow parsnip.

Cow parsnip is native to North America and can be found throughout much of the country, according to the U.S. Fish and Wildlife Service. It comes the closest in size to giant hogweed, reaching heights of 4 feet to 9 feet tall, but it’s not as wide, usually maxing out at about 1 foot wide rather than up to 5 feet wide for giant hogweed.

Cow parsnip also blooms with clusters of small, white flowers. Its flower clusters typically range between 6 inches and 12 inches wide, and the stems of the plant are grooved and covered with fuzz.

Contact with cow parsnip can cause skin irritation and discoloration as well as a blistering rash. As with giant hogweed, it’s best to avoid contact with the plant or to wear protective clothing and gloves.

Wild parsnip

Closeup of wild parsnip.

Wild parsnip looks like Queen Anne’s lace and many of its look-alikes with one key difference: It is yellow, not white. Wild parsnip is often confused for golden alexander, a native wildflower that produces similar-looking yellow, lacy flowers. One of the easiest ways to differentiate between the two is height. While wild parsnip can reach heights of 4 feet to 5 feet, golden alexander is smaller, growing to about 3 feet tall. And while golden alexander is typically in bloom between April and June, wild parsnip blooms later in the season.

You should avoid contact with wild parsnip, a non-native invasive plant, because it can cause a painful rash. That's because wild parsnip sap contains a substance called psoralen, which, when it comes into contact with skin in the presence of sunlight, can cause a severe, blistering rash that can take weeks to heal and leave scars.


Giant Hogweed

Closeup of giant hogweed.

This plant is among the nastiest of all, but luckily it remains relatively rare in Illinois, according to the University of Illinois Extension. Giant hogweed is native to Asia and an invasive species here in the United States, likely introduced because of its use as a spice. So far, it has only been identified in a few Illinois counties, but its range continues to expand.

Giant hogweed is, indeed, giant, regularly reaching heights of 10 feet to 15 feet tall and 5 feet wide, according to the U.S. Fish and Wildlife Service. It has thick, hollow stems that can be 2 inches to 4 inches thick. The stems have vertical ridges, and they often have brownish or purplish spots on them. It produces small, white clusters of flowers that typically bloom between May and July.

Contact with sap from giant hogweed in the presence of sunlight can cause severe skin and eye irritation, leading to blistering rashes, permanent scars and blindness. It’s best to avoid handling this plant, the University of Illinois Extension advises. If you must handle it, always wear protective clothing and gloves to ensure your skin does not make direct contact with the plant and its sap.

Spotted water hemlock

Closeup of spotted water hemlock.

Spotted water hemlock is native to North America and widespread across the United States. It is similar in appearance to Queen Anne’s lace, with both having clusters of small white flowers. Water hemlock is typically taller than Queen Anne’s lace, measuring between 3 feet and 6 feet tall. The stems of this plant can vary in color from green to purple or green with purple spots or stripes.

While coming into contact with these plants poses no risk for skin irritation or rashes, consuming any part of spotted water hemlock can be deadly, the U.S. Fish and Wildlife Service warns. In fact, it is widely considered the most deadly plant in North America. Ingesting water hemlock can cause convulsions, delirium, seizures, nausea, vomiting and abdominal pain, and can result in death.

Poison hemlock

Closeup of poison hemlock's stem showing the purple spots and blotches.

Poison hemlock is similar in appearance to spotted water hemlock and Queen Anne’s lace and is closely related to Queen Anne’s lace, according to the University of Illinois Extension. This plant, which is native to Africa, Asia and Europe but invasive in North America, has the small, lacy flower clusters like the other two plants, but it grows taller — reaching 3 feet to 8 feet tall — and has hollow stems with purple spots and blotches.

Poison hemlock is often confused for water hemlock, and while both are toxic to humans and many animals, poison hemlock is not as dangerous. Still, consuming any part of the plant is poisonous and in severe cases can cause death, the U.S. Fish and Wildlife Service advises.


Lead image: Wild parsnip

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