RUTACEAE 



RUE FAMILY 



SHRUBBY TREFOIL. HOP TREE 



Ptclea trifoliata L. 



Ptelea is the Greek name of the Elm and is applied 



to this genus because of its similar fruits. 



The Hop Tree is a tall shrub or small tree which is found in 

 rocky places from New 

 York and Ontario to 

 Minnesota and south- 

 west. It has many local 

 names, some of which are 

 Wafer Ash, Shrubby 

 Trefoil, Swamp D o g - 

 wood and Wingseed. Of 

 no economic importance, 

 it is frequently culti- 

 vated as an ornamental 

 shrub and its bark was 

 formerly much used in 

 medicine. 



The small greenish 

 white flowers that appear 

 in June are usually very 

 ill scented, the odor 

 resembling that of a 



skunk, but fragrant flowers are occasionally found. Stamens and 

 pistils are always present but the stamens in one form (the 

 pistillate flowers) are small and do not produce pollen, whereas in 

 the other form the pistils are dwarfed and functionless. Petals 

 and sepals are 2-'^ ^nd the number of stamens is the same as the 

 number of petals. The pistil consists of a 2-celled ovary, a short 

 style and 2 stigmas. The fruit, which matures in August or 

 September, is a 2-seeded samara, well adapted to wind dissemi- 

 nation. It is very bitter and is sometimes used as a substitute 

 for Hops. 



A form of this Hop Tree more common in Illinois is Ptelea 

 trifoliata L. var. mollis T. & G. Practically the only diflPerence 

 is in its thickish leaflets, which are densely and permanently 

 downy on both surfaces. The Lake Michigan shore is probably 

 the preferred habitat of this variety in Illinois, and it is known 

 in woods from Long Island to Florida and Minnesota to Texas. 



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