156 ANACARDIACEAE 



sessile, oblong to linear-oblong, often falcate, 1 14 to 5 inches 

 long, and up to \]4. inches wide. They are narrowed or rounded 

 at the base and acuminate at the apex, and their margins are 

 finely or coarsely serrate. At maturity they are dark green and 

 smooth above, or nearly so beneath, except on the midrib and 

 the main vein. 



The inflorescence is a dense, terminal panicle up to 12 inches 

 long, which comes into flower in June and July. The flowers 

 are greenish yellow, those bearing stamens being about ]/s inch 

 in diameter, and the margins of the petals are not glandular- 

 ciliate. The fruit matures in August and September as a small, 

 bright red drupe densely covered with long red hairs; and 

 the light browTi, slightly flattened seed is smooth and oblique. 



Distribution. — The Staghorn Sumac prefers sandy or 

 gravelly ridges and slopes or bluffs, and sometimes it grows in 

 moist situations about lakes and bogs. It ranges from New 

 Brunswick to North Dakota and south to Georgia and Missis- 

 sippi. In Illinois, it is widely distributed throughout the north- 

 em part of the state, being especially abundant in the north- 

 east in the vicinit}- of Lake Michigan. Elsewhere it is rare and 

 local, and has been recorded at Starv^ed Rock in La Salle 

 County, in Morgan Count}-, Cass County, Hancock County 

 and along bluffs of the Apple River in Jo Daviess County. 



RHUS GLABRA Linnaeus 

 Smooth Sumac 



The Smooth Sumac, fig. 37, is an upright shrub commonly 

 4 to 12 feet high, with branchlets which are, by the end of the 

 year, more or less keeled below the buds and with compound 

 leaves 12 to 20 inches long. The leaf rachis is smooth, except 

 for a pubescent line above, and the leaflets generally number 

 15 to 25. The lateral leaflets are sessile or nearly so, and the 

 terminal ones are short-stalked. The blades are oblong-ovate 

 to lanceolate-oblong, 2 to 4 inches long by l/^ to 1 14 inches 

 wide, and acuminate at the apex. Terminal leaflets are nar- 

 rowed or rounded at the base; lateral leaflets are oblique and 

 rounded at the base. The margins are rather coarsely serrate 

 and the leaf surface is green and smooth above, except along 

 the midvein, and smooth and glaucous beneath. 



The inflorescence is a large, terminal, pubescent panicle, and 



