Poisonous plants New York are ones that would ruin your day whether you are having fun in your backyard, in a field, or taking a day off to hike trails. Some cause minor irritations, while others can lead to more severe complications like permanent scars.

7 Poisonous Plants New York

But how do you identify these poisonous native plants? What do they look like? You will find these answers in a short while.  

List of Poisonous Plants New York to Avoid

1. Giant Hogweed

Giant Hogweed

  • Flat oval leaves
  • Purple splotches
  • Clustered white flowers
  • Riverbanks
  • Yards and gardens
  • Roadsides
  • Streams
Poisonous Parts
  • Stem
  • Leaves
  • Bad burns
  • Permanent scars
  • Blindness 

Giant Hogweed, one of the most attractive plants during summer with its flat-white top cluster of white flowers, tops the list of the most poisonous plants in that is found in New York. It has a sap, mainly found in the plant’s leaves and stem, reduces your skin’s natural protection against sunlight. Even worse, the fluid can cause blindness if it enters your eyes.

If you get into contact with Heracleum mantegazzianum, or the giant Hogweed, you can always clean the area with soap and cold water, very quickly. Since the affected area has reduced protection against the sun, cover yourself when going outside. 

On the other hand, it can get more severe if the sap gets into your eyes, it can cause blindness, and this would show you how dense the poisonous sap is. Which means that you must make sure that you rinse the eyes with water and see a physician if there are reactions. 

2. Poison Ivy
Poison Ivy

  • Three glossy leaflets
  • Yellow flowers with white berries
  • Woody vine that appears as a shrub
  • Woodland edges
  • Landscapes
  • Gardens
Poisonous Part 
  • Leaves
  • Stems
  • Roots
  • Itchy rash
  • Severe blistering

Although poison ivy can be identified with its three leaves that grow as a vine or small shrub, it is easily confused with other plants. The leaves are glossy and smooth, and some contain toothed edges. They are green when young and during summer, and they turn red in spring. The plant produces white flowers and yellow berries. 

Poison ivy’s oily leaves cause a rash on human skin, leading to severe blisters in some people. These symptoms can take up to 24 hours however, if it is more abundant, then it can take more than a day, which means that you must take cautiousness and make sure that you rinse your skin immediately after contacting this plant.

You should also wash your clothes to remove the oil and avoid scratching the skin. Applying calamine lotion or cool compresses to the affected part can reduce the itching. 

3. Stinging Nettle

Stinging Nettle

  • Stinging hairs on the stem, leaf stalks, and veins
  • Dark green leaves growing in pairs on the stem
  • Clusters of flowers near the base of the leaves
  • Relieve arthritis pain
  • Manage diabetes
  • Reduce seasonal allergies
Poisonous Part
  • Stem
  • Leaves
  • Intense burning on the skin
  • Irritation
  • Itching

Although stinging nettle is a medicinal plant, it is one of the invasive species to avoid. When the stinging hairs on its leaves and stems come into contact with your body, they cause intense burning and irritation. 

The plant produces histamine, serotonin, and formic acids responsible for these effects, as these would come from the sap, and how it is abundant of this liquid.

You will notice the stings with raised bumps on the skin, which would start to feed agitated at first. You can prevent more irritation by avoiding touching the affected part. In addition, wash the skin with soap and water, and remove any left-over fibers using tape. 

Although stinging nettles are poisonous, they have medicinal benefits as well. For example, the plant relieves arthritis symptoms like inflammation, gout, and osteoarthritis. They also help to reduce seasonal allergies like those caused by pollen. On the other hand, if you use stinging nettle for medicinal benefits, ensure you contact your doctor first. 

4. Cow Parsnip

Cow Parsnip

  • Round, hairy leaves with coarsely toothed leaflets
  • Rough, hairy, hollow stems
  • White or cream flowers
  • Flowers have five petals
Medicinal Uses
  • Cures cold and sore throats
  • Alleviates tuberculosis symptoms
  • Treats indigestion
Poisonous Parts
  • Leaves
  • Stems
  • Skin irritation
  • Blistering 

Identified with its hollow, grooved stem and hairy tri-segmented leaves, cow parsnip is one of the Northeast poisonous plants. The plant commonly grows in forest openings, grasslands, river edges, and roadsides. 

Cow Parsnip has a poisonous sap found in all parts of the plant. When your skin touches the leaves or stem, the plant produces a fluid that causes phototoxicity. This increases your skin’s sensitivity to sunlight, causing sunburns, blisters, and skin irritation, which means that it is very rich in its toxic sap if you get close to it, the effects would be quite severe. 

In order to avoid getting in contact with cow parsnip, wear gloves when handling trees around it, or other protective gloves that can handle being impermeable towards this poisonous plant. In addition, you should also wash the affected area with cold water to prevent skin irritation. 

Although these plant parts are poisonous when they rub your skin, they are edible and have medicinal benefits, however, it is a big challenge if you wish to do so on your own and have no expertise in the field.

The young leaves are tender and can be cooked, while the older foliage can be a wrapper for food. Moreover, the plant also treats colds, sore throats, tuberculosis, and indigestion, but you must get instructions from your doctor first. 

5. Poison Sumac

Poison Sumac

  • A multi-stemmed shrub with grey bark
  • Red, smooth, compound leaves
  • Yellow flowers
  • White berries
  • Swamps
  • Peat bogs
  • Wet areas
Poisonous Parts
  • All parts
  • Leaves are poisonous even after the plant dies
  • Itching
  • Burning sensation
  • Swelling
  • Watery blisters

Poison sumac is one of the rare poisonous plants. It grows mainly in wet areas, and its effects resemble poison ivy. The plant’s rarity makes it hard for New York plant state identification, but you can use its leaves and flower characteristics to spot it. It is known as the red variation is not poisonous but the green one definitely is. 

Poison sumac has an oily substance called urushiol that comes out when the plant is bruised. The oil causes allergic reactions to the skin, leading to itching, burning sensations, and even causing some blisters to your skin.

Urushiol also remains in clothes, skin, and shoes, so it can cause symptoms in another person if not washed, or if you wear them the next time and feel itchy, this is the key reason why. 

Keep in mind that once exposed to poison sumac, clean the clothes and wash the affected skin thoroughly with soap and cold water. Using warm water causes the oil to spread more, causing more irritation towards you which would feel tiring. 

The rush does not have a cure, but you can apply calamine lotion, hydrocortisone creams, and menthol to alleviate the symptoms. You should see a doctor if the rash spreads to your genitals or face and if you suffer a high fever.

6. Wild Parsnip

Wild Parsnip

  • Grooved, hairless five feet tall stems
  • Yellow, clustered flowers with a flat-topped array
  • Compound leaves with three to five leaflets
  • Open areas
  • Roadsides
  • Disturbed areas
  • Pastures
Poisonous Parts
  • all parts of the plant
  • causes phototoxicity
  • Skin reddening
  • Blisters
  • Burning sensation

This plant is also one that is related to giant hogweed and cow parsnip, however the wild parsnip is one of the plants to be avoided or else the cause is greater than most. It produces a toxic sap to the skin called furanocoumarins, which causes phototoxicity, which is when this area of the skin that got contaminated by the sap, and then exposed to light, it would feel a severe burn. 

In short, the skin becomes more vulnerable to ultraviolet rays, leading to severe burns, irritation, and reddening in the affected areas. The area also suffers sunlight sensitivity for years, so you must protect it throughout.

When you get into contact with wild parsnip, wash the area thoroughly using cold water and soap. Which means that you can also remove and clean the clothes and cover the skin to protect it from direct sun rays. 

7. Poison Oak

Poison Oak

  • Vine-like shrub with three leaves
  • Yellow or green flowers
  • Green-yellow or white berries growing in clusters
  • Wooded or mashy areas
  • Mountains
  • Valleys 
  • Food for herbivores
  • Outcompetes with other invasive plants to reduce their spread
  • Rush
  • Blisters

If you have been wondering, is there poison oak in New York, the short answer is yes, as this is one of the most commonly found toxic plants that can be found. Poison hemlock New York (read more about poisonous plants in virginia) causes similar reactions to human skin as poison ivy and poison sumac. These plants have urushiol that causes skin itchiness, rushes, and blisters. 

The plant is identified with green leaves that have three leaflets and a fuzzy underside. It grows as a shrub and produces white or yellow berries. But where is poison oak found? (guide about Plants that look like poison oak) This poisonous plant mainly grows in marshy and wooded areas, mountains, and valleys. 

Although it causes rashes and blisters, poison hemlock is food for herbivores. Its tender, nutrient-rich leaves and stems nourish animals like black-tailed deer and rabbits. If the plant releases urushiol to your skin, wash the affected part with cold water and soap. It is good to know that you should also clean your clothes and avoid exposing your skin to the sun, so that the toxins would be washed off. 


Poisonous plants New York are hardly noticeable because they resemble other usual plants. These plants cause different reactions when they come into contact with the human body. From the article, you have learned that:

  • Giant Hogweed is one of the most poisonous plants in New York. It leaves permanent marks and can cause blindness if it gets into contact with the eyes.
  • Some plants, like stinging nettle and cow parsnip, have medicinal benefits. They can be used to treat tuberculosis, sore throat, and arthritis.
  • Poison ivy, poison sumac, and poison oak have similar effects and characteristics.
  • With the many types of plants available, identifying the poisonous ones can be challenging. However, knowing characteristics like the type of foliage, flowers, stem, or smell the plant has can help you identify the dangerous ones.

If your skin gets into contact with these plants, wash with cool water and soap. You can see a physician if the symptoms persist. 





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