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While the natural world is full of wonders, it also contains many dangers. In addition to insects and creatures that can bite or sting, there are poisonous plants that can cause severe discomfort or injury with just a touch. Some plants are found only in the wild, while others are grown in ornamental gardens or kept as houseplants.
To help you keep these toxic wonders of nature at arm’s length, we’ve put together a comprehensive list of poisonous plants you should never touch.
1. Poison Ivy (Toxicodendron Radicans)
Poison ivy is a trailing plant that climbs upwards or along the ground, covering everything in its path. This fast-growing poisonous plant grows widely across the U.S., particularly in wooded areas and along the edges of fields.
Contact with poison ivy causes severe itching, redness, and blisters, and medical treatment is often required. The effects of poison ivy are typically temporary but can be extremely uncomfortable and sometimes lead to secondary infections
from scratching.
2. Poison Oak (Toxicodendron Diversilobum)
Poison oak is commonly found in the western U.S., especially in forests and along trails. This shrub has a climbing habit and bears leaves in clusters of three that resemble oak leaves. Contact with poison oak results in itching, redness, and blisters, and the effects, although temporary, can be very distressing.
3. Poison Sumac (Toxicodendron Vernix)
Poison sumac is closely related to our first two entries and causes similar effects. This woody shrub is found in wet, swampy areas of the eastern U.S. and is identified by its smooth, hairless leaves and clusters of small berries. The effects of poison sumac are temporary but can be severe and often require medical treatment.
4. Giant Hogweed (Heracleum Mantegazzianum)
Giant hogweed is a towering plant with large, umbrella-shaped clusters of white flowers and enormous leaves. It grows in the northeast and northwest U.S. and thrives in moist environments such as riverbanks, forest edges, and ditches. Contact with giant hogweed sap in conjunction with sunlight exposure causes severe skin burns that can result in permanent scarring.
5. Wild Parsnip (Pastinaca Sativa)
Wild parsnip is a tall plant with yellow, umbrella-shaped flower clusters. It thrives in fields and roadsides throughout the U.S. and can be identified by its grooved stems and celery-like feathery leaves. Contact with the sap of wild parsnips, combined with sunlight exposure, can cause severe skin burns and blisters, and medical treatment is recommended to reduce the risk of lasting scars.
6. Stinging Nettle (Urtica Dioica)
Stinging nettle is a perennial herb that grows in moist, nutrient-rich soils across the U.S. The plants have heart-shaped serrated leaves and tiny stinging hairs along the main stem and side shoots.
Contact with stinging nettles causes a painful, burning sensation and skin irritation, often with redness and swelling. Medical treatment is not usually required, but antihistamines and soothing creams can help alleviate symptoms.
7. Cow Parsnip (Heracleum Maximum)
Cow parsnip is closely related to giant hogweed and causes similar, albeit less severe, effects. This large plant can easily be identified through its white, umbrella-shaped flower clusters and large, lobed leaves. Contact with cow parsnip sap, combined with sunlight exposure, can cause severe skin irritation, blisters, and long-lasting scars, and medical treatment is recommended for severe reactions.
8. Poison Hemlock (Conium Maculatum)
Poison hemlock is a tall plant with small white flowers in umbrella-like clusters, commonly found in areas of disturbed soil throughout the U.S. Contact with poison hemlock can cause skin dermatitis, and the plant is also highly toxic if ingested.
The effects of touching poison hemlock is usually temporary but can be very uncomfortable, and medical treatment is recommended for severe skin reactions.
9. Monkshood (Aconitum spp.)
Monkshood is a tall plant with hood-shaped blue or purple flowers, normally found in the northern U.S. and mountainous areas. Contact with monkshood sap can cause numbness, tingling, and severe cardiac issues if absorbed through cuts or mucous membranes. The effects can be temporary but potentially serious, and immediate medical treatment is essential.
10. Dumbcane (Dieffenbachia spp.)
Dumbcane is a common houseplant with large, variegated leaves and thick, cane-like stems. Its sap can cause intense irritation and swelling if it gets on the skin and is transferred to the mouth or eyes. The effects are usually temporary but very painful, and medical treatment is often required for severe reactions.
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11. Angel’s Trumpet (Brugmansia spp.)
Angel’s trumpet is a small tree with large, pendulous, trumpet-shaped flowers in shades of white, yellow, pink, or orange. It is found in warm climates of the southern U.S. and contact with the sap can cause skin irritation. If transferred to the mouth or eyes, the sap can lead to more serious symptoms such as hallucinations and paralysis, and medical treatment is recommended for severe exposure.
12. Rhododendron (Rhododendron spp.)
Rhododendron is an evergreen shrub with large, showy flowers in a variety of bold colors. Contact with rhododendron leaves or flowers can cause skin irritation, redness, and swelling. Medical treatment is usually unnecessary, but soothing creams can help alleviate symptoms.
13. Spotted Water Hemlock (Cicuta Maculata)
Spotted water hemlock features small white flowers in umbrella-like clusters and is found in wet areas such as marshes and stream banks. Contact with spotted water hemlock sap can also cause dermatitis and skin irritation, which is extremely toxic if ingested.
14. Oleander (Nerium Oleander)
Oleander is often found in gardens and roadsides and bears fragrant white, pink, or red flowers. Contact with oleander sap can cause skin irritation and more serious health issues if it enters the bloodstream through cuts. The effects can be temporary but potentially serious, and medical treatment is recommended for severe exposure.
15. Foxglove (Digitalis Purpurea)
Foxgloves are a biennial plant with tall spikes of tubular flowers in shades of purple, pink, or white. Contact with foxglove leaves or flowers can cause skin irritation, and if sap enters the bloodstream, it can lead to serious cardiac issues.
16. Yellow Jessamine (Gelsemium Sempervirens)
Yellow jessamine is a vining plant with yellow, trumpet-shaped flowers and shiny, lance- shaped leaves. Contact with its sap can cause skin irritation and more serious symptoms if it enters the bloodstream through cuts. The effects can be temporary but potentially serious, and medical treatment is recommended for severe exposure.
