4 BULLETIN 706, U. S. DEPARTMENT OF AGRICULTURE. 



of 30 feet and trunk diameter of 10 inches. The leaflets are dark 

 green, smooth on top, paler and often hairy underneath, with edges 

 smooth or few-toothed toward the apex. The fruit grows in dense 

 terminal clusters, is crimson in color, and is covered with fine hairs. 

 The unmistakable characteristics of this species are the winged 

 growth along the leaf stem between the leaflets (PI. II, A) and the 

 black specks on the new stalk. Dwarf sumac grows in dry soil, and 

 may be found from Maine and southern Ontario to Florida and 

 Texas, and west to Minnesota and Nebraska. 



WHITE SUMAC, sometimes called SMOOTH, UPLAND, or SCARLET 

 SUMAC (Rhus ylabra) . A shrub, or rarely a small tree, 2 to 20 feet 

 high. The leaflets are dark green on top and whitish underneath, 

 with edges sharply saw-toothed. The fruit grows in dense terminal 

 clusters, and is covered with short reddish hairs. The distinguishing 

 characteristics 'of this species are the smoothness of the stalks and 

 leaf stems, together with a bluish white bloom, a powdery film similar 

 in appearance to that found on plums, which covers the stalks and the 

 under side of the leaflets (PL III). White sumac grows in dry soil 

 from Nova Scotia to British Columbia, and south to Florida, Missis- 

 sippi, and Arizona. 



STAGHORN SUMAC, sometimes called HAIRY SUMAC (Rhus hirta). 

 A shrub, or small tree, with maximum height of 40 feet and 

 trunk diameter of 9 inches. Leaflets, dark green and nearly smooth 

 on top, pale, and more or less hairy underneath, with edges sharply 

 saw-toothed. The fruit, which grows in dense terminal clusters, is 

 thickly covered with bright-crimson hairs. The distinguishing 

 characteristic of this species is the hairy growth along the stalks and 

 leaf stems (PL IV) . Staghorn sumac is found in dry and rocky soils 

 from Nova Scotia to Georgia, especially among the mountains, and 

 as far west as southern Ontario, Minnesota, Missouri, and Mississippi. 



Since poison sumac sometimes is mistaken for the more common 

 species, and its poisonous effects are usually very severe, it seems 

 desirable to describe it as an aid in distinguishing poison sumac 

 from the other species. 



POISON SUMAC, sometimes called POISON ELDER (Rhus vernix). 

 A shrub, or small tree, with maximum height of 28 feet and trunk 

 diameter of 6 inches. The leaflets are green on top and underneath, 

 with edges smooth. The fruit, which grows in loose, open clusters, 

 consists of smooth white or light gray berries. It should be noted 

 that poison sumac differs decidedly from the important species in 

 the color and cluster formation of its fruit. Furthermore, it may 

 be easily distinguished from the dwarf sumac by the absence of the 

 winged growth along the leaf stems, and from the white and stag- 

 horn sumac by its smooth-edged leaflets (PL V). Poison sumac 

 almost invariably is found in swamps. It grows from southern 



