By Debbie Gilbert

JUNE 8, 1998:  It’s the scourge of the South: an aggressive vine that can take over entire forests and is tough to eradicate. No, we’re not talking about kudzu here, but poison ivy, a plant apparently put here by God to make us miserable.

But it doesn’t have to ruin your summer. Once you know the facts about poison ivy, you shouldn’t have to worry about contracting the rash. Here are some of the most common misconceptions about it:

Myth: I’ve never had poison-ivy rash, so I must be immune.
Fact: You can become allergic to poison ivy at any point in your life, and the more you’re exposed to the plant, the higher the likelihood you’ll become sensitized. At least half of all Americans react to it.

Myth: Highly sensitive individuals can get poison ivy just by standing near it.
Fact: The rash is caused by a toxic oil, urushiol, which you can get only by touching either the plant or something else that has touched it, such as shoes, clothing, or pets. (If you let your dog run loose in the woods, she becomes a Typhoid Mary, collecting urushiol and sharing it with you.)

Myth: You can only get poison ivy in the summer.
Fact: All parts of the plant are potentially toxic at all times. You can recognize the vines in winter because they’re “fuzzy,” covered with short, hairy tendrils. Watch out for these when gathering logs for firewood. When the plant is burned, urushiol becomes airborne and can be inhaled into the lungs, causing life-threatening inflammation of the breathing passages.

Myth: Scratching the rash will make it spread.
Fact: The fluid in poison-ivy blisters is not contagious, and touching the sores will not transfer the rash to another part of the body, or to another person. The reason poison ivy seems to appear in stages is multiple exposures; you may have made contact with urushiol at several different times. The rash shows up 12 to 72 hours after exposure. It often has a linear, streaking appearance because the plant has brushed along your skin. The blisters will weep and ooze and itch like crazy for about two weeks. In severe cases, you may develop a secondary bacterial infection requiring antibiotics.

But avoiding this torture is simple: Just don’t touch the plant. That means knowing what it looks like, and this can be tricky for the uninitiated, because poison ivy has variable forms. It can be a vine, a free-standing weedy plant, even a small tree. Its leaves can be glossy or dull, and their edges can be smooth or serrated.

If you aren’t sure about identification, the old adage “Leaves of three, let it be” is a good rule to follow. The leaves are arranged in a distinctive triangular pattern, with two leaves directly opposite each other and the third sticking out in front, perpendicular to the lower two. Don’t worry about distinguishing this plant from poison oak; the latter is rare in the Memphis area, and usually what people call “poison oak” turns out to be poison ivy or a baby oak tree.

Poison ivy loves disturbed, marginal areas, such as the edge of a forest that’s been partially cut, so it’s very common in the suburbs. There’s no good explanation for why poison ivy tends to take over certain places. For example, it’s rampant at Nathan Bedford Forrest State Park, on the Tennessee River, but almost nonexistent at Mousetail Landing State Park, also on the Tennessee but farther south. If you want to get away from Toxicodendron radicans altogether, you’ll have to travel to Alaska, Hawaii, or the deserts of California and Nevada, or climb above 4,000 feet.

But let’s get real. Around here, you have to live with this stuff. And that means watching where you’re going. In the woods, stay on trails – preferably at least 2 feet wide. Don’t reach out to steady yourself against a tree trunk until you’ve checked it for fuzzy vines.

If your skin encounters poison ivy despite your efforts, you’ve got a grace period of about 15 minutes in which to wash it off, using water, alcohol, or a product called Tecnu (which can also be used to clean urushiol off clothing, shoes, equipment, even pets).

You also now have the option of preventing poison-ivy rash. Last year the FDA approved IvyBlock, a lotion that forms a protective film over your skin, making it almost impervious to urushiol.

IvyBlock is available without a prescription at any pharmacy. It can be a godsend, but there are drawbacks. First of all, it’s pricey: about $9 for a 4-ounce bottle. It has to be reapplied every four hours, so you could go through a bottle pretty quickly. And if you’re in the typical summer-outdoors situation where you also need sunscreen and insect repellent, that’s three layers of crud you’ve got to slather onto your skin.

When precautions fail and a raging rash develops, time-tested remedies are still the gold standard. Calamine lotion eases itching and helps dry up weeping blisters. Cool baths with a half-cup of baking soda or Aveeno oatmeal added to the tub can be soothing, especially if the rash covers large areas of the body. Cool compresses with diluted Burow’s solution (ask your pharmacist) may be helpful. Nonprescription steroid creams such as Cortaid are often effective, but should be used only for a few days at a time.

If the rash is widespread, if there is swelling, or if the eyes are affected, you should see a doctor. You will probably be prescribed both a corticosteroid lotion (more powerful than what you can buy over the counter) and a steroid pill such as prednisone to reduce inflammation.

But it should never come to that. People who are vigilant and use common sense hardly ever get a case of poison ivy that bad.

The best advice is to stay out of the woods, right? Well, no – the biggest risk is to gardeners. According to the Journal of the American Medical Association, reactions to poison ivy and oak are the leading reason for worker’s-compensation payments to people who work outdoors. And weekend gardeners can get into trouble in their own backyards. Don’t just yank out the offending vines; spray them first with an herbicide such as Roundup, ideally in the growing months of June and July. Wait a week, until the plant is dead down to the roots, then put on gloves and bag the vines for disposal (don’t burn them!). If the poison ivy is surrounded by desirable plants and you don’t want to use weedkiller, you may have to wait until fall and cautiously pull the ivy up by its roots.

In any case, it will soon be back. Poison ivy loves the South. Unlike the invasive kudzu, poison ivy is a native species. It’s in its element here, and there’s nothing you can do except learn to co-exist with the enemy.

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