poison oak


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poison oak

n.
1. Either of two plants, Toxicodendron pubescens, a shrub of the southeast United States, or T. diversilobum, a shrub or vine of western North America, having compound leaves with three lobed or toothed leaflets, and causing a rash on contact.
3. A skin rash caused by contact with one of these plants.
Pharmacognosy A plant—Rhus diversilobium (western poison oak) or Rhus diversiloba (eastern poison oak)—that is highly allergenic due to urushiol
Public health A popular term for any allergic reaction or dermatopathy caused by Rhus diversilobium or Rhus diversiloba

poison oak

A type of hypersensitivity dermatitis caused by Rhus diversiloba–western poison oak, and R quercifolia–eastern poison oak. See Poison ivy.

poi·son i·vy

, poison oak , poison sumac (poy'zŏn ī'vē, ōk, sūmak)
2. Common name for the cutaneous eruption caused by contact with these species of Toxicodendron.
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POISON OAK

poison oak

A climbing vine, Toxicodendron diversiloba, closely related to poison ivy and having the same active substances.
See: illustration
References in periodicals archive ?
Birds nested most often in coast live oak (Quercus agrifolia; n = 17 of 46) and poison oak (Toxicodendron diversilobum; n = 11 of 46), the predominant canopy and understory plants, respectively, in many areas of dense forest.
Indeed, Carolina confirmed she had been extremely allergic to poison ivy, and possibly poison oak, as a child: Once it was so bad that my eyes were swollen shut.
'Poison Oak': I may have gotten a touch/of poison oak hiking in low heels/on sharp rock.
Lead article of this issue is "When a Child Hurts Other Children." Other topics include: Norovirus and Stomach Flu; Breath-holding; Healthy Drink Choices; Infant Formula and Flouride; Poison Oak; Pinworms; and Upcoming Legislation.
If you are allergic to poison ivy, poison oak and poison sumac will give you the rash, as well.
Just be careful of snakes, which love to hide in the vines, and be sure not to pick poison ivy or poison oak, which have the same three-leaf arrangement.
ORDER OF THE POISON OAK. The summer after he "came out" and began a gay-straight alliance at his school, Russell looks forward to being a counselor at a camp where no one knows him.
Visit Brent's Brain (http:// brentsbrain.livejournal.com/), the blog spot for Brent Hartinger, author of Geography Club, Order of the Poison Oak, and The Last Chance Texaco.
Two of YA's biggest success stories are Brent Hartinger, whose newest book is The Order of the Poison Oak, and Alex Sanchez, whose Rainbow series--Rainbow Boys, Rainbow High, and Rainbow Road, due in October--has had huge crossover popularity.
The source of this myth may be that the poinsettia was confused with poison ivy or American poison oak (Rhus radicans), which turns bright red in the autumn.