POISON IVY, OAK AND SUMAC 



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minutes. Severe scrubbing with a brush is not advisable, 

 but several swabs or small compresses of gauze may be 

 used, discarding each in turn, so that the poison may not 

 be distributed by the cloth. 



Bathing with alcohol diluted with an equal amount of 

 water is also an effective preventive. Where exposure 

 has been more general, a bath for the entire body, fol- 

 lowed by a change of clothing, is a good preventive 

 measure. The hair should not be neglected. Bathing, if 

 not accompanied by sufficient changing of water or 

 rinsing, may result in spreading the rash to skin that had 

 not been infected. In cases that are at all serious a 

 physician should be consulted. 



The investigators call attention to the fact that scores 

 of remedies and prescriptions are more or less in popular 

 favor, but in spite of the claims they assert that no 

 specific treatment for poisoning from ivy and sumac is 

 yet available. Ointments should not be used in the acute 

 stage of the disease. In the later stages, however, sooth- 

 ing and astringent ointments may be of value in allaying 

 irritation and hastening cure. The extent to which it is 

 desirable to use solutions of permanganate of potash, 

 hyposulphite of soda, sulphate of magnesium (Epsom 

 salts), and other remedies, is also discussed. Sugar of 

 lead, formerly much used, often proves disappointing if 

 applied after inflammation has developed, and the user 

 runs the risk of lead poisoning if this substance is 

 applied extensively. 



The names "poison oak" and "poison ivy" are used 

 interchangeably in many localities. The plant generally 

 known as poison oak throughout the Pacifie Coast occurs 

 as a bush, sometimes four or five feet high, and has 

 leaflets resembling the leaves of the western oak, but it 

 is also found as a vine, and is sometimes called poison ivy. 



In the East from New Jersey, Delaware, and Virginia 

 southward the name "poison oak" is often used to dis- 

 tinguish from the poison ivy vine, a form occurring as 

 a bush with lobed leaflets, a little resembling the leaves of 

 scrub oak. Westward from Minnesota, Nebraska, and 

 Arkansas to Washington, Montana, Colorado, and New 

 Mexico this name is applied to a low bush or trailing 

 shrub which does not climb. The leaves of all forms have 

 stout, rather long stems bearing three leaflets, two of 

 which are opposite and short stalked, while the third has 

 a long stalk. The leaflets are from one to four inches 

 long, dark green on the upper surface, lighter (sometimes 

 with a velvety covering of fine hairs) underneath, with 

 smooth or somewhat indented margins. 



In the Eastern States and westward as far as Wyom- 

 ing to Texas the Virginia creeper is found generally in 

 the same location as poison ivy vine, which it resembles 



somewhat in its habits and the shape of its leaflets; but 

 it can be readily distinguished from poison ivy in that 

 its leaves are divided into three to five leaflets to the stalk. 

 Moreover, though it is sometimes supported by aerial 

 rootlets, like poison ivy, it also has numerous tendrils 

 like those of the grape vine, and its inedible fruits are 

 blue, with red stems, and contain two or three seeds. 



Poison sumac grows in moist ground, usually in 

 swamps or along low, miry banks of streams and ponds. 

 It occurs from New England to Florida, and westward 

 to Minnesota, Arkansas, and Louisiana. The poison 

 sumac leaves are readily distinguished from the harm- 

 less sumac and species of ash, elder, and other shrubs 

 and trees, having a somewhat similar foliage, and the 

 character, appearance, and color of the fruits furnish 

 other simple means of identification. Furthermore, the 

 poison sumac occurs on moist or swampy land, and in 

 drier locations is found only along the borders of swamps 

 or bogs. The number of leaflets into which the leaves of 

 the harmless sumacs are divided range from 9 to 21 and 

 31, while the poison sumac leaves divide into 7 to 13 

 leaflets. 



While many persons are of the opinion that contact 

 with these plants is not necessary to produce poisoning, 

 it is probable that many cases supposed to have originated 

 in this way have actually been due to direct or indirect 

 contact. There are cases on record showing that the 

 smoke from burning plants will give rise to irritation, and 

 in some cases severe poisoning has resulted from this 

 form of exposure. Regarding the popular belief that 

 some persons are wholly immune, the investigators state 

 that there is good reason to believe absolute immunity 

 does not exist, although it is recognized that some persons 

 are much less susceptible than others. 



Eradication of these plants should be widely undertaken 

 and followed up systematically. Every landowner should 

 feel a measure of responsibility in this matter. The 

 simplest method is by grubbing, in which care should be 

 taken to cover the hands properly, and also to prevent 

 infection by means of the clothing. 



The plants in fields may be destroyed by plowing them 

 up and putting in cultivated crops. Often repeated 

 mowing is also effective. The use of kerosene is recom- 

 mended where injury to other plants or trees is not to 

 be feared. It may be applied with a sprinkler or a 

 spraying pump, and in many cases one application is 

 sufficient. Arsenate of soda has been used very suc- 

 cessfully to kill poison ivy on trees 6 to 10 inches in 

 diameter without injury to the trees, as well as on stone 

 walls, buildings, and along fences. 



