Janet moved into her "dream home" in October. Her lake-view property was dotted with stately oak trees. But, there was only one thing she couldn't stand--those ugly vines that had climbed high into the trees. All the leaves were off the trees, and the vines were brown and withered. So, why did she develop a rash on her face, neck and arms?

Don had hiked and hunted in the Alabama outdoors since he was a child. As an adult, he worked surveying those same woodlands. He knew about poison ivy--how to identify it and to stay away from it. So, why was he sitting in the emergency room with a rash that wouldn't go away?

Robert had previously inspected the area that he and the crew would be surveying. Although the land was a little marshy, this job was a surveyor's dream--a rolling field spotted with patches of blue and yellow wildflowers and every now and then a clump of tall green plants with little greenish-white blooms. So, why were the men scratching their arms and elbows all the way back to the office that afternoon?

Contact Dermatitis

The American Academy of Dermatology estimates that 85 percent of the people exposed to poison ivy, oak or sumac will develop an allergic reaction. These susceptible people develop a skin rash that doctors call contact dermatitis.

Each person reacts a little differently to each plant. One person may come in contact with large amounts of a particular plant and have no reaction at all while another person will merely brush by a plant and be affected almost immediately. Typically, the allergic response to poisonous plants occurs 12 to 48 hours after exposure. However, some people develop a rash in as short as 4 hours and others as long as 10 days.

It is important for surveyors, and others who work outdoors, to learn as much as they can about wildflowers and plants.

Poison Ivy and Poison Oak

Urushiol is the offending chemical in poison ivy and poison oak. This oily liquid is transferred to a person's skin when the person touches the leaves or stems of these plants. Usually, a rash will not appear until several days after contact. Medical experts say that if all the oil is washed off the skin within five minutes of contact, there should be no reaction.

Poison ivy is a vine that is found in urban and rural settings throughout the United States. It has rich green leaves that grow in groups of three. During the fall and winter poison ivy vines lose their leaves and turn a lifeless-looking brown. However, they are far from harmless even in this dormant stage. Many people like the new homeowner mentioned at the beginning of this article are taken by surprise when they try to destroy the vines. Urushiol remains active in leaves, roots, and vines--no matter what season. Reports indicate that work tools and surveying instruments can retain active urushiol for two years or more.

Poison oak is a bush that simulates poison ivy in its appearance and its wrath. The leaves of poison oak look more like oak leaves and the undersides of the leaves are always a much lighter green than the top. Although it is most often found in the western portion of the nation, poison oak has been reported in many other parts of North America as well. In some areas poison oak and poison ivy grow so close together that they cross pollinate and develop a variant plant.

Poison Sumac

Although this plant also contains urushiol, medical experts and those with firsthand experience say it can cause a more irritating rash.

Poison sumac is a shrub or short tree that likes swampy, uninhabited areas. The tree itself grows to only five or six feet in height. Each limb is covered with seven to thirteen oval-shaped leaves with one leaf at the end of the limb. This poisonous tree produces drooping clusters of green berries.

Poison sumac has a harmless cousin that produces red, upright berry clusters.

Don, the surveyor mentioned at the beginning of this article, had never encountered poison sumac. The swampy, secluded land that he was clearing was covered in this lovely green plant.

Stinging Nettle

In Latin, Nettle means "I burn" and does it ever.

The men in Robert's survey crew, mentioned at the beginning of this article, were plagued with stinging nettle. This plant grows just the right height to contact hands and elbows of people setting up surveying equipment. Coming in contact with this plant can cause much the same experience as coming in contact with cactus.

Stinging nettle's stems and heart-shaped, serrated leaves are covered with tiny needle-like hairs. When a person touches these plants, the tiny hairs break off, releasing formic acid--the same stuff that gives ant bites their sting.

Contact with these little needles cause immediate irritation followed by white, itchy bumps. The rash usually lasts from one to 24 hours.

Pretty Flowers with a Mean Streak

You would expect a plant like Mother-in-Law's Tongue, also called a Snake Plant, to be irritating--and it is. But what about those colorful little flowers that grow so beautifully in neighborhood flower beds and along roadsides?

Beware of pretty flowers. Those sweet yellow buttercups that tell us spring is finally here are not always so sweet after all. Handling the bulbs, stems, and blooms of buttercups, daffodils and narcissus can cause contact dermatitis.

Queen Anne's Lace, also known as wild carrot, carries a punch also. This tall plant with white blooms that form a large saucer-shaped flower decorate country roads throughout the nation. Even though all parts of this plant are eaten at certain times of year, collecting the little buggers can cause a person to contemplate the joy of cooking.

Fall's beauty, Chrysanthemum is another deceiving flower. Substantial contact with the leaves, stem and blooms of this plant can cause an irritating rash for many people.

Other common flowers and plants that cause contact dermatitis include dog fennel, Jack-in-the-pulpit, wild ginger, Jimson weed, larkspur, yellow jessamine, trumpet vine, brown-eyed Susan and oleander.

A Friendly Flower

Surveyors should make friends with jewelweed. This colorful bush-like plant with rich green leaves and small red and yellow blooms sparkles in morning dew causing people to think of a diamond necklace accented with red and yellow gems.

This lovely lady is more than a pretty bush. Crushed jewelweed leaves will quickly soothe the itch of a rash. Some herbalists believe that continued applications of crushed jewelweed will even quicken the healing process.

Learn more about poisonous plants

Protect yourself

  • Wear high-top boots and long plants with the cuffs tucked into the boots.

  • Wear long-sleeved shirts with the bottom tucked into your pants.

  • Wear gloves.

  • Apply barrier protection such as bentoquatam (brand name IvyBlock), available over the counter at many drugstores.

  • Clean machetes, bushaxes, and other equipment that has come in contact with the poisonous plants.

  • Clean the soles and sides of your boots.

  • If possible, change clothes before getting back into the truck.

  • Wash contaminated clothing and gloves--separate from other clothing--using detergent and hot water.

If your skin comes in contact with the plant

  • Flood the area with cold water, and soap if available, to remove as much of the plant's oil as possible.

  • If there is no water available, you can remove the plant's oil by rubbing your skin with dirt or sand. (NEVER rub dirt or sand on an area where there is a cut, broken skin or blisters.)

Relieving the itch

  • Rub crushed jewelweed on the affected area.

  • Briefly apply a wet tea bag to the area or pour unsweetened tea over the rash.

  • Apply a paste made out of either oatmeal, baking soda, or cream of tartar.

  • Apply cold compresses--wet washcloths or ice packs.

  • Run cool water over the affected area.

  • Topical creams such as Zanfel may provide some relief.