Many common vines contain compounds harmful to humans and pets. These vines can cause reactions from skin irritation to severe internal issues, depending on the plant and exposure. Understanding their potential risks is important for outdoor safety.
Identifying Dangerous Vines
Poison Ivy (_Toxicodendron radicans_) is recognized by its compound leaves that typically grow in clusters of three, leading to the saying, “Leaves of three, let it be.” Leaflets can be shiny or dull, with smooth, wavy, or toothed edges, and their color varies from green to red seasonally. It grows as a climbing vine with hairy, aerial roots or as a low-spreading shrub, producing small, greenish-yellow flowers in spring and white or off-white berries in late summer. All parts of the plant contain urushiol, a resin responsible for allergic reactions.
Poison Oak (_Toxicodendron diversilobum_ or _Toxicodendron pubescens_) also contains urushiol and has a “leaves of three” growth pattern. Its leaves often have a lobed or scalloped appearance, resembling oak leaves, and may be fuzzy. Poison oak grows as a shrub or climbing vine, producing yellowish-green flowers and light green to off-white berries.
Virginia Creeper (_Parthenocissus quinquefolia_) is often mistaken for poison ivy but typically has five leaflets radiating from a central point, though sometimes three or seven are present. A helpful mnemonic is “Leaves of five, let it thrive.” This vine uses tendrils with adhesive disks to climb surfaces and produces dark blue or black, grape-like berries in late summer. Its berries and leaves contain oxalic acid and saponins, which can be harmful if ingested.
Morning Glory (_Ipomoea spp._) is a common ornamental vine with heart-shaped leaves and funnel-shaped flowers that open in the morning. While not a contact irritant, the seeds of certain species contain lysergic alkaloids. These compounds are toxic if ingested and can cause adverse effects.
Recognizing Exposure Symptoms
Contact with urushiol, found in poison ivy and poison oak, typically causes allergic contact dermatitis. This manifests as a red, itchy rash, often with swelling, bumps, and fluid-filled blisters. The rash may appear in streaks where the plant brushed against the skin, developing within 12 to 48 hours and lasting for several weeks. Scratching the rash can lead to skin infection.
Ingestion of poisonous vine parts can lead to internal symptoms. Consuming Virginia Creeper berries or leaves, which contain oxalic acid and saponins, can cause immediate irritation of the mouth, lips, and tongue. This may be followed by nausea, vomiting, abdominal pain, and in severe cases, difficulty swallowing or breathing or kidney damage.
Ingesting Morning Glory seeds can cause gastrointestinal upset, including vomiting and diarrhea. The lysergic alkaloids in the seeds can also lead to neurological effects such as confusion, tremors, dilated pupils, and hallucinations, particularly if large quantities are consumed. Symptoms from ingestion can vary in severity based on the amount consumed and individual sensitivity.
Safety Measures and What to Do
Preventing exposure involves awareness and protective measures. When in areas where these plants might be present, wear long sleeves, long pants, closed-toed shoes, and gloves. Barrier creams containing bentoquatum can offer additional skin protection. Avoid burning plant debris that may contain poisonous vines, as inhaling the smoke can cause severe respiratory issues. After outdoor activities, thoroughly clean any tools or clothing that may have come into contact with the plants, as urushiol can remain active on surfaces.
If exposure occurs, prompt action can minimize the reaction. Immediately rinse affected skin with rubbing alcohol, a specialized poison plant wash, or degreasing soap and plenty of water. Scrub under fingernails to remove lingering oils. If a rash develops, applying wet compresses, calamine lotion, or hydrocortisone cream can alleviate itching and blistering. Oral antihistamines may also provide relief.
Seek professional medical attention if the rash is severe, widespread, covers sensitive areas, or if blisters ooze pus, indicating infection. Difficulty breathing, swelling, or signs of a severe allergic reaction warrant immediate emergency medical care. For suspected ingestion, especially in children or pets, contact a poison control center or seek immediate medical attention.