HEALTHWATCH / POISON OAK : Hiker’s Itch Spreading Fast : The dreaded plant has sprouted a lush growth this year due to abundant rains.

It lies there innocently, not making a sound, not moving, just waiting in some shady location--maybe along a stream bed or beneath an oak tree. If you’re not careful, you’ll miss it, maybe even walk right through it.

That’s when the trouble begins.

Of course, you won’t know it for a while. Give it a day or so. Then the rash will appear. And the itching will start.

At least that’s the case for the estimated 85% of the population who suffer allergic reactions to the dreaded poison oak. And thanks to this winter’s heavy rains, this plant, like many others, is growing more rapidly and in greater abundance than in recent years.

“It’s not that it’s suddenly spread into new places. It’s just that it’s growing real well,” said Jerry Revard, botanist for the city of Ventura.

“It’s going to be creeping onto trails. When you get accelerated growth, say six inches where you might normally get two or three inches, it’s going to grow out in the pathways that much faster.”

Add to that the fact that people are taking advantage of the recent sunny skies to venture outdoors, and the chance for exposure to poison oak increases. Thousand Oaks dermatologist Dr. Ralph Kamell has seen proof of this. He said his poison oak-related business has increased considerably of late.

Kamell explained that the itchy rash many folks experience after contact is an allergic reaction to the plant’s oil. “If you’re already allergic to it,” he said, “the rash develops the next day and it spreads because you spread the oil on your skin.” If you’re not already allergic to it, you may become allergic to it.

Obviously, the sooner the poison oak is washed off the skin, the lesser the chance of its spreading over the body. Revard suggests using a soap called Phelsnaptha. The oil, unfortunately, can also spread to clothing and, Revard said, can stay on the material for up to a year if not washed away.

Though the traditional treatment of poison oak might be TLC and calamine lotion, doctors can take more aggressive approaches. Kamell said rashes can be treated with a prescription cortisone that should decrease the duration of the rash, which can last up to four weeks. Hospitalization may be required due to excessive oozing, but that, he said, is extremely rare.

The best way to avoid the discomfort of poison oak, of course, is to avoid contact with it. In case you’ve forgotten your childhood warnings, here’s a description of the typical suspect.

Poison oak has a smooth stem and each of its shiny, generally oval leaves is divided into three parts. The leaves, which are crinkled around the edges, are green or red-orange. In the summer, poison oak produces a white berry slightly smaller than a pea.

The plant’s oil is found on its leaves and stem, so the plant can be a hazard even in the winter, when the leaves have fallen off and only a gray stem remains.

Now that you’ve got poison oak on your mind--and hopefully not on your hands--it’s as good a time as any to mention another plant found in Ventura County that is best left alone: stinging nettles.

“The plant is associated with stream beds and wet areas,” Revard said. “Since we’re going to have more types of those areas you can expect to see more types of nettles. They’ll be growing vigorously now.”

Though the nettles are uncomfortable, they do not have as long-lasting an effect as poison oak. Revard said the typical reaction is a few hours of burning and itching. “They are little cells with needles on the end with a bulb at the base filled with formic acid,” he said. “When you hit them, they inject a little bit of the acid into the skin.”

Revard said nettles can reach eight feet in height. They usually have an upright stem covered with spines, giving them a fuzzy appearance. The leaves, which can grow up to six inches, are serrated around the edges and also are covered with spines.

On the plus side, Revard said, “young growth, if cooked, is a good green. And the stems can provide good fiber for cordage.”