This undated photograph provided by the U.S. Centers for Disease Control and Prevention shows a black-legged tick, also known as a deer tick, a carrier of Lyme disease. CDC via AP File photo

For those spending much of their time in the great outdoors this summer, being able to tell poisonous plants in the wild apart from harmless plants may be the difference between life and death.

Pennsylvania’s wilds are crawling with flora and fauna that are deadlier than they look, and could cause serious health problems to unsuspecting hikers, bikers and other vacationers who come in contact with them — anything from nasty skin rashes to abdominal pain and even death.

Common finds include poison ivy oak, and sumac, which are capable of delivering blistering skin rashes to those who come in contact with them.

This undated image provided by Bugwood.org shows poison ivy growing in Hubbard County, Minnesota. Steven Katovich/Bugwood.org via AP

Dustin Drew, manager of both Moraine and McConnells Mill state parks, said that poison ivy is a common sighting at both parks.

“We do remove it or treat it with herbicide if found in high use areas, but it is very prevalent throughout trails and forested areas,” Drew said.

In addition, Pennsylvanians can run into highly toxic native plants, such as the wild parsnip. Although the parsnip is usually cultivated in controlled environments, their seeds can spread to roadsides and ditches where they can grow in the wild. In their wild form, parsnips are covered in sap that can cause blisters upon contact with human skin.

Another threatening plant is the giant hogweed, whose buds excrete a sap that can cause human skin to become extra-sensitive to ultraviolet light, causing burns and blisters. If the plant comes in contact with human eyes, it may even result in permanent blindness.

“ (Giant hogweed) can be identified by its height and purple splotches and course bristles,” said Diane Dallos, master gardener coordinator for Penn State Extension of Butler County. “It can grow in disturbed soils along waterways, roadsides and vacant lots.”

Some native plants, such as water hemlock, can only harm humans who choose to ingest them. The plant contains a chemical called cicutoxin which, if ingested, can cause muscle convulsions and seizures, and eventually death.

The similar-looking poison hemlock is loaded with poisonous alkaloids. Those who ingest the plant can suffer symptoms immediately, including high blood pressure, rapid heartbeat, seizures and even paralysis.

“Poison hemlock is probably the plant we are focusing on the most right now that has potential health impacts to humans,” Drew said. “We are actively treating a population in our Lakeview area on the north shore (of Moraine State Park) with herbicide.”

Poison ivy and similar plants can easily be identified thanks in part to the common rhyme, “Leaves of three, leave it be.” However, in some cases, it can be difficult to tell one toxic plant from another. Such is the case with the giant hogweed and the water hemlock, both of which are toxic and are made up of small, white flowers with purple-spotted stems.

Making matters even more difficult, both plants can also be confused with the far less toxic purple-stemmed angelica.

But the most dangerous creatures in Pennsylvania’s woods are arguably not the giant hogweed, or deer, or even the occasional bear, but ticks. “Ticks are a big concern, as they can cause Lyme disease, Rocky Mountain Spotted Fever, Tularemia rabbit fever, Alpha-gal allergy and many other conditions,” Dallos said.

The Keystone State is home to at least 25 species of tick, including the black-legged tick, American dog tick and lone star tick — all of which are capable of carrying deadly diseases.

“Summer is the active season for black-legged tick nymphs, American dog ticks and lone star ticks, but it is important in our climate to be vigilant year-round,” Dallos said.

Pennsylvania is a hotbed for Lyme disease, which is spread by the black-legged tick. According to the Centers for Disease Control, the Keystone State had the second-highest number of Lyme disease cases of any state in 2023 with 16,671, trailing only New York’s 22,173.

The characteristic symptoms of Lyme disease include, but are not limited to, a bullseye shaped rash, flu-like symptoms and swollen lymph nodes.

“The best prevention is dressing properly,” Dallos said. “Tuck pant legs into socks or boots and tuck shirts into pants and gloves. Consider wearing white or light-colored clothing so ticks are more visible.”

Dallos also recommends treating clothing with tick repellent solutions such as permethrin, picaridin and oil of lemon eucalyptus.

“Anyone who is subject to a tick bite can submit the tick for testing to the Pennsylvania Tick Research Lab,” Dallos said.

For those who have their skin exposed to a plant that can cause skin rashes or blisters, be sure to thoroughly wash the affected area with a good soap and warm water. Calamine lotion is a tried-and-tested method for dealing with itching from poison ivy and other treatments, such as anti-itch cream, are also available.

In the worst-case scenario, it never hurts to have the number for poison control on hand. The nationwide poison control number is 1-800-222-1222.