We know many of thempoison ivy and oak, for examplebut some take us by surprise.

Study and keep an eye out for these plants when hiking or enjoying time in nature.

Most importantly, be sure to keep your distance.

Poison Ivy (Toxicodendron radicans)

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If you need toevaluate a plantthat you think might be poisonous, be sure to do so visually.

Don’t touch it unless you have gloves on.

Read on for 10dangerous plants and weedsyou should never touch.

Hogweed (Heracleum mantegazzianum and H. sphondylium)

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This chemical reaction occurs after exposure to sunlight, where the sap touches the skin.

The result is painful, severe blisters on the surface of the skin.

If it comes into contact with the eyes, it can also cause blindness.

Manchineel (Hippomane mancinella)

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It has the reputation of being the world’s most dangerous tree, and for a good reason.

The sap contains irritants that create a blistering reaction upon contact with the skin.

It’s a reminder to stay away from thispainful and skin-irritating three-leaved vine.

Poison Oak (Toxicodendron diversilobum)

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Poison Oak

This woody vine is in the sumac family and packs a painful punch.

Poison oak is sometimes mistaken for poison ivy.

Its leaves, which look much like oak trees, can distinguish it and its shrub form.

Poison Sumac (Toxicodendron vernix)

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Poison Sumac

Poison sumac is a woody shrub found in wetland areas.

Touching it is also a direct route to a painful rash.

In the South, it’s also commonly known as thunderwood.

Stinging Nettle (Urtica dioica)

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It also has clusters of green berries.

Harmless sumac, on the other hand, has red berries.

Stinging Nettle

Pain and itching follow a brush with stinging nettle.

Deadly Nightshade Atropa Belladonna

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Covered in tiny stinging hairs, its leaves and stems release irritants when they come into contact with skin.

Touching these needle-like spines will make skin sting (hence the name) and sometimes break out in inflammation.

The red berries make this perennial vine.

Poison Hemlock

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Bittersweet nightshade can spread along the ground or train to climb structures, trees, or other vertical fences.

This plant was brought to North America as an ornamental species and is native to Eurasia.

Native to Europe and North Africa, poison hemlock resembles parsley but can be dangerous if consumed.

Deadly Nightshade

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The toxins also absorb through the skin, so wearing gloves is always essential when assessing this weed.

This perennial plant has long branches and oval-shaped, smooth leaves.

The unique flowers are a shade of purple and green, blooming from June to September.

Jimson Weed

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Deadly nightshade also displays blackberries, but these are also very toxic.

This plant is toxic, and the seeds contain alkaloid compounds that can be deadly if ingested.

The flowers of jimson weeds are white or violet and trumpet-shaped, producing a spiny fruit.