poison sumac

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poison ivy

poison ivy, poison oak, and poison sumac, woody vines and trailing or erect shrubs of the family Anacardiaceae (sumac family), native to North America. They are sometimes considered as several species of Rhus, the sumac genus, but are usually distinguished as Toxicodendron radicans (poison ivy and poison oak) and the larger T. vernix (poison sumac). The whitish berrylike fruits often persist through winter. The leaves of T. radicans are composed of three smooth leaflets. Both species have vivid red autumn foliage. Poison oak is a name generally used in the South and West for the bushy kinds.

The irritant principle, urushiol, is present in almost all parts of the plant. Direct or indirect contact (clothing, tools, or animals that have touched the plant, or smoke from burning the plants) sets off a skin eruption that may vary from simple itching inflammation to watery blisters, depending upon the sensitivity of the individual. The eruption appears within a day to two weeks depending upon sensitivity. It begins on the portion of the body that has come in contact with the plant, usually the hands, which then can spread it to the face and other areas. Washing contaminated skin as soon as possible after contact can reduce the severity of symptoms. These plants are classified in the division Magnoliophyta, class Magnoliopsida, order Sapindales, family Anacardiaceae.

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poison sumac

poison sumac

The fuzzy berries are WHITE. Do not touch.
Edible Plant Guide © 2012 Markus Rothkranz

poison sumac

[′pȯiz·ən ′sü‚mak]
Rhus vernix. A tall bush of the sumac family (Anacardiaceae) bearing pinnately compound leaves with 7-13 entire leaflets, and drooping, axillary clusters of white fruits that produce an irritating oil.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
Poison ivy, poison oak, and poison sumac are common plants in many regions of the United States and Canada.
Poison ivy, poison oak and poison sumac grow almost everywhere in the United States, except Hawaii, Alaska and some desert areas of Nevada.
A The main poisonous plants that give people trouble are poison ivy, poison oak, and poison sumac. The tricky thing is that poison ivy can look a different in different parts of the country.
A history of exposure to common contact allergens, such as a recent run-in with poison ivy, poison oak, or poison sumac, may be all that is needed.
Cade Laboratories is one of the companies offering treatment for exposure to poison ivy, poison oak or poison sumac that goes beyond just treating the itch and other symptoms.
They are very different than the poison sumac. Poison sumac has whitish berries that hang down, and it is kind of rare.
You don't know it yet, but you've just joined at least 2 million other Americans who, this summer, will become all too well acquainted with the power of poison ivy or one of its near relatives--poison oak and poison sumac. Sometime within the next six to 96 hours, you're likely to find yourself agonized by an itching, watering rash on your back, neck, face, arms, legs and--um, elsewhere.
Poison oak and poison sumac are closely related to poison ivy.
The most common cause of allergic skin reactions is exposure to poison ivy and its "first cousins" poison oak and poison sumac. There are many misconceptions about these plants, all species of the plant genus Rhus, and the problems they can cause.
Poison ivy usually grows east of the Rockies, and poison sumac east of the Mississippi River.
They are named for Euro-Americans (Engelmann spruce, Picea engelmannii) and Native Americans (Giant Sequoia, Sequoiadendron giganteum), for poisons (poison sumac, Toxicodendron vernix) and for sweets (sugar maple, Acer saccharum).
This useful plant is not to be confused with three sumacs that grow wild in North America, all of which can cause severe dermatitis: poison oak, poison ivy, and poison sumac.