Identify Poison Sumac

Poison sumac, or Toxicodendron vernix, is a plant native to the eastern United States and Canada. Most people develop a painful allergic reaction upon contact with any part of the plant, resulting in a red, itchy rash or blisters. Learn how to identify poison sumac by its appearance and habitat, so you can avoid this painful fate.

Steps

Identifying Poison Sumac

  1. Look for a sparse shrub or tree. Poison sumac typically grows into a shrub or tree about 5–20 ft (1.5–6 m) in height, but may occasionally grow even taller. The branches may or may not be covered with leaves along their length, but either way the growth pattern of poison sumac tends to produce a fairly open result, rather than a thick bush of foliage.[1]
    • Large poison sumac trees, like other species of sumac, often grow long, thin branches that sag or tilt downward.[2]
  2. Watch for small plants with upward pointing leaves. Before poison sumac grows into a full sized shrub or tree, it may be relatively upright, with small branches with red stems growing along the entire height of the trunk. In this case, its leaves and branches usually have a noticeable upward tilt, especially near the top of the tree.[2]
  3. Look for double rows of leaves on each stem. Poison sumac has a pinnate leaf structure, meaning that each stem has two parallel rows of leaves growing along its length. Each stem usually has between six and twelve leaves, plus an additional single leaf at the end.[1] Young stems are typically red or red-brown, but this color may fade to brown or grey as the plant ages.
    • Technically, the leaves of a pinnate leaf are called leaflets, but these look like an ordinary leaf, roughly 2–4 inches (5–10 cm) long.
  4. Recognize the leaf shape of poison sumac. The leaves of this plant have an oval or oblong shape, tapering to a wedge or point on each end. The sides of the leaf may appear wavy or smooth, but will not have the jagged "tooth" appearance of some non-poisonous sumac trees.[2]
  5. Learn the other attributes of the leaf. Poison sumac is deciduous, so the leaves change color throughout the year. Newly grown spring leaves may be bright orange, becoming light green during spring and summer, changing to red during autumn, then falling off the plant entirely.[1] The underside of poison sumac leaves, at any time of year, may be either smooth or hairy, making it a poor way to identify the plant.
    • Warning: The fallen leaves may still be poisonous to the touch. Never burn leaves or wood collected near a poison sumac tree, as inhaling poison sumac smoke can be dangerous or even fatal.[3]
  6. Identify poison sumac flowers. During the spring and summer, poison sumac may have pale yellow or green flowers.[3] These small flowers grow in clusters along their own, green stems, separate from the red leafy stems.[2]
  7. Identify the berries. During summer or fall, the plant may have replaced its flowers with small green or yellow berries. Over the course of the fall and winter, these will mature into clusters of white and grey berries, hanging down on stems up to 12 inches (30 cm) long.[2]
    • If the berries are red, and the rest of the plant fits the description above, the plant is most likely a non-poisonous member of the sumac family.[4]
    • The berries may be eaten by animals or fall off naturally during winter. Do not assume they will always be present.
  8. In winter, look for white berries or empty berry stems. Poison sumac is still poisonous without its leaves, but it can be much harder to identify. If you're lucky, it will still have hanging clusters of white or pale yellow berries which you can use as a warning sign. After the first few weeks of winter, however, you are more likely to see thin, empty stems hanging from the branches, similar in appearance to light brown grape stems.
  9. Avoid grey bark found in poison sumac habitat. Identifying the poisonous bark of poison sumac can be difficult once all the foliage and berries have fallen off. Use the habitat section below to know which areas sumac may grow in, and steer clear of any trees with rough, grey bark.

Recognizing Poison Sumac Habitat

  1. Know the regions where poison sumac can grow. Unlike its relatives, poison ivy and poison oak, poison sumac is restricted to a fairly small area of the world. If you are outside the following areas, your chance of encountering poison sumac is almost zero:[5]
    • Ontario, Quebec, and other eastern provinces of Canada
    • Minnesota, Wisconsin, and all U.S. states east of them, including all of New England
    • Illinois, Kentucky, Tennessee, and all U.S. states east of them, including all of the South
    • Texas, and all states east of it along the southern U.S. border, including Florida
  2. Look for poison sumac in moist or flooded soils. Poison sumac thrives in unusually wet soil, or even in standing water. If the surrounding area is dry throughout the year, there is little chance that poison sumac is present.
    • During dry weather, keep an eye out for empty riverbeds or dried mud that indicate the area may usually be wet.
  3. Don't worry about poison sumac at high elevations. Poison sumac has trouble growing at 4,000 ft (1,200 m) above sea level or above.[6] If you are above 5,000 ft (1,500 m), there is almost no chance of exposure to poison sumac.
    • Its relatives, poison ivy and poison oak, are also constrained to low elevations, reducing the need for caution concerning poisonous plant exposure at high altitudes.

Treating Poison Sumac Exposure

  1. Consider using a towel soaked in rubbing alcohol immediately after exposure. If you identify poison sumac and know you have been exposed, pour rubbing alcohol over the affected skin as soon as possible. Because the toxin, urushiol, will not fully dissolve in alcohol, using a paper towel or other solid material to rub the alcohol-soaked skin may be necessary to remove a significant amount of the toxin.[7]
    • Warning: the alcohol may temporarily make you more susceptible to further exposure, by removing the protective oils on your skin. Avoid areas where poisonous plants grow for the next 24 hours after applying alcohol, if possible.
    • A better alternative is using a good surfactant to bind the oils before they penetrate the dermis of the skin, Fels Naptha (old fashioned yellow soap available at a hardware store) or good ole Spic n Span, wash the affected areas well, scrub and rinse well. Repeat. Do not touch any affected clothing as the oil will remain on the surface and readily transfer to skin.
    • Wear disposable gloves during this process if your hands have not been exposed.
  2. Wash in water. Whether or not you applied alcohol, scrub the exposed area with lots of water. You may also use soap, detergent, or specialized products such as Tecnu, but wash these off frequently so they do not dry on your skin along with any toxin they have picked up.[3]
  3. Treat the rash with antihistamines or lotions. If you develop blisters or a rash, you may take oral antihistamines to reduce the itching. You may also apply calamine, hydrocortisone lotions, or oatmeal baths for the same purpose.
    • If you develop large, oozing blisters, you may wish to visit a doctor for prescription-strength treatment.
    • Ooze from blisters does not contain the toxin, so it cannot spread the rash.
  4. Seek medical attention in severe cases. If you suspect you inhaled poison sumac smoke, seek medical attention immediately even if symptoms have not developed. Other serious situations that may require a doctor's attention include a rash on your face or genitals, or a rash anywhere that fails to reduce in size after a week.[3]
  5. Wash exposed tools and clothing. If you leave the sumac oil on tools or clothing, they can spread the rash for months or years after the initial exposure. Put on disposable gloves and wash tools with soap and water, rubbing alcohol, or diluted bleach. Store clothes in disposable bags during transport, then wash them in soap and hot water.

Tips

  • The best way to avoid developing a rash through contact with poison sumac is to wear long sleeves, long pants, and closed-toed shoes when walking outdoors.
  • The toxin urushiol is the allergy-inducing agent in poison sumac, poison ivy, and poison oak, although it is usually most concentrated in poison sumac. People can become allergic to urushiol over time, so do not assume you are safe if you fail to develop a rash once.

Warnings

  • Never burn plant matter taken from an area where poison sumac grows. Inhaling the oil from poison sumac plants can cause serious respiratory harm, or even death.

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Sources and Citations