Itch to Hike Might Lead to Poison Oak

It’s going to be a good year for poison oak, which is bad news for anybody who is contemplating tripping through the woods.

The wet winter has produced a bumper crop of the nefarious plant. Poison oak is just beginning to leaf, and is abundant and omnipresent in L.A.-area mountains and forests, particularly on cooler north-facing slopes.

“This year will be worse than normal,” state Ranger Frank Padilla said.

Contact with poison oak can cause a severe rash that lasts about 10 days. The plant oozes a sap containing an irritant called urushiol, which is sticky and virtually invisible and can even be carried in the wind. Because the sap adheres to everything except water, it can be present even though the plant is not.

Once urushiol touches the skin, it penetrates in minutes, but rashes won’t occur for another 12 to 48 hours, lulling the victim into a false sense of security before the itching begins, often in the middle of a deep sleep.

The general rule has always been, “Leaves of three, let them be,” but not all varieties of poison oak fit that description. To minimize your risk on hikes, Padilla suggests wearing gloves, long pants and long-sleeve shirts. Afterward, he says, buy a degreasing agent, such as Tecnu, at a pharmacy and wash with tepid water. It might not prevent a rash, but it will limit the severity of an outbreak.