THE DOGWOOD OR POISON SUMACH 



FORTUNATELY the Poison Sumach can be easily known at any season : in summer 

 and autumn the many leaflets with smooth margins and with the main leaf-stalk 

 not winged enable one to identify the species ; in winter and spring, the grayish- 

 ^hite berries in drooping clusters and the smooth bark of the branches serve a similar 

 purpose. The importance of knowing and avoiding the plant need not be urged upon 

 any one who has been poisoned, or has known others to be poisoned, by its leaves or twigs. 

 For this is the most virulent of our contact-poisoning plants and its effects upon persons 

 susceptible to harm from it are often very severe. It is not always necessary even that 

 it be touched ; the mere passing by has been known to cause the characteristic irritation 

 of the skin. Some people, however, are immune and may handle all parts of the shrub 

 with impunity. In general the danger seems greatest when one is perspiring freely. 



As a rule the Poison Sumach is a branching shrub ten to fifteen feet high, growing 

 in groups which are likely to attract attention by the brilliant beauty of their autumnal 

 foliage. Frequently, however, it grows into a small tree, perhaps twenty feet high. It is 

 generally to be found along the borders of swamps, and occurs over a great region, extend- 

 ing from Maine to Alabama on the east, and Minnesota to Louisiana on the west. As 

 compared with the other Sumachs, the flowers, which blossom in early summer, are in 

 small clusters. 



In his "Report on the Trees and Shrubs of Massachusetts," George B. Emerson 

 wrote many years ago : " The near resemblance in all the properties of the Poison Sumach 

 to those of the Varnish-yielding Sumach of Japan, has led to the belief that a similar 

 substance might be procured from it. To this end Dr. Bigelow made, in 1815, several 

 experiments which seem to establish this point in a manner very satisfactory. A quantity 

 of the juice was boiled alone, until nearly all the volatile oil had escaped, and the remainder 

 was reduced almost to the state of a resin. In this state it was applied while warm to 

 several substances, which after cooling exhibited the most brilliant, glossy, jet-black sur- 

 face. The coating appeared very durable and firm, and was not affected by moisture. It 

 was elastic and perfectly opaque, and seemed to answer the purposes of both paint and 

 varnish. The poisonous property, as in most cases of vegetable poisons, seems to be 

 removed by evaporation or boiling, and the dry varnish would probably be innocuous." 



The species has other names than Poison Sumach: in some localities it is the 

 Dogwood or Poison Dogwood ; in others it is the Poison Elder or the Poison Ash. It has 

 also at least two accepted scientific names: in Sargent's Manual, Linne's Rhus vernix is 

 accepted; in the "Cyclopedia of Horticulture" De Candolle's R. venenata is used. 



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