What is Poison Oak?

Poison Oak is a shrub-like form of poison ivy and is a member of the cashew family, Anacardiaceae.

Poison Oak from the southeastern United States is called Rhus quercifolia, and its leaves are divided into three leaflets with dense hair and three to seven lobes. The poisonous fruit is white and berry-like and are somewhat hairy. On the Pacific coast, the poison oak variety is Rhus diversiloba. It is shrubby or sometimes a climbing plant with three-leaflet leaves and toothed leaves that are hairless. Both species are poisonous, just like apoison ivy. The plant is generally found at elevations under 4,000 feet (1,200 meters).

The chemical in poison oak is urushiol and it is found in all parts of the plant. When you touch it, the oil of the poison is absorbed into the skin and a rash results. The rash is the consequence of your body trying to fight off the poison.

You can get a reaction by touching any part of the poison oakplant and if your pet has wandered through it and you touch the pet, you can also get the infection. Interestingly, pets are immune to the condition. You can also get poison oak from touching your clothing if it contains even trace amounts of urushiol.

Once you have absorbed the poisonous oil into your skin and the rash appears, you will not spread the rash by scratching. This is because the rash is directly caused by your immune system, not from the poison itself. The oil that may ooze from the rash is not the poisonous urushiol, but an oil secreted from your own body. You may think that you are spreading the infection by scratching, but you are not.

The best way to avoid poison oak is to recognize it and, when you come home from a hike, wash everything you were wearing — including your shoes!

Poison oak is a plant primarily found in North America known for causing skin irritation upon contact. It can be identified by its leaves, which grow in clusters of three and resemble oak leaves, with a variable green to red color depending on the season. The leaves have a shiny surface and may have white or yellow berries.

Poison oak contains urushiol, an oily resin that triggers an allergic reaction in most people. Contact with the skin results in an itchy, blistering rash. According to the American Skin Association, about 85% of the population is allergic to urushiol, making poison oak rashes quite common among those who come into contact with the plant.

If you come into contact with poison oak, immediately rinse the affected area with lukewarm water to remove the urushiol oil. Avoid using soap initially, as it can spread the oil. Afterward, wash with soap and water. Apply calamine lotion or hydrocortisone cream to soothe the rash, and consider seeing a doctor if the reaction is severe.

Poison oak rash cannot spread through the blister fluid, but it can seem to spread if urushiol oil remains on the skin or is transferred from contaminated clothing or objects. It's not contagious from person to person unless urushiol oil is present on the skin or clothing and comes into contact with another person.

Poison oak is commonly found in wooded areas, grasslands, and chaparral environments in North America, particularly on the West Coast, Southeast, and in the Appalachian region. Look out for its distinctive leaf clusters, avoid bushy areas, and stay on clear paths when hiking to minimize the risk of exposure.

To safely remove poison oak, wear protective clothing, including gloves, long sleeves, and goggles. Do not burn the plant, as inhaling the smoke can cause severe respiratory problems. Instead, carefully dig out the plants, ensuring you remove the roots to prevent regrowth. Dispose of the plants in plastic bags and wash your clothes and tools thoroughly afterward.