76 Forest Trees and Shrubs of Meriden, Conn. 



132. RHUS GLABRA. (Linn.) 



Common or Smooth Sumach. 



A shrub, growing from three to eight feet high. Fruit red, but 

 in an open and spreading cluster. Flowers in June. Fruit in Sep- 

 tember and October. 



133. RHUS COPALLINA. (Linn.) 



Dwarf Sumach. 



A shrub, from eight to ten feet in height, found on the borders 

 of woods. Wood soft, coarse grained, satiny, susceptible of a good 

 polish. Leaves and bark astringent, rich in tannin. Fruit acid 

 and astringent, and used medicinally in the form of decoctions, 

 fluid extracts, etc. Specific gravity, 0.5273; ash, 0.60. 



134. RHUS VENENATA. (De Candolle.) 



Poison Sumach. Poison Elder. Swamp DogAvood. 



A rather handsome shrub, sometimes a small tree from eight to 

 ten feet high. A worthless shrub, and exceedingly poisonous to 

 many persons, but some can handle it with impunity. Opposite 

 effects are sometimes produced on different members of the same 

 family. The poisonous effect is owing to the presence of a volatile 

 principle, Toxicodendric acid. Wood soft, coarse-grained. The 

 white, milky sap turns black in drying, and yields a lacquer simi- 

 lar to the Japan varnish, which is supposed to be obtained from a 

 similar species. Specific gravity, 0.4382 ; ash, 0.64. 



135. RHUS TOXICODENDRON. (Linn.) 

 Poison Ivy. Poison Oak. Poison Vine. 



Usually a clinging plant, but sometimes with stem two to five or 

 six feet high. Less poisonous than the R. venenata. Always 

 readily distinguished by its leaves and fruit. Flowers in May and 

 June. Fruit in September. 



XXIX. RUTACE^. The Rue Family. 



136. XANTHOXYLUM AMERICANUM. (Miller.) 



Prickly Ash. Yellow Wood. Toothache Tree. 



Shrub from four to six feet high, but wlien cultivated and 

 trimmed forms a tree sometimes twenty feet high. Wood light, 



